Image forming device management system

ABSTRACT

An image forming device management system includes a plurality of image forming devices, a central service station which provides a maintenance service for the image forming devices, and a communication control unit which is connected to each of the image forming devices by a signal line, the communication control unit connecting one of the image forming devices to the central service station via a communication network. In the system, each of the image forming devices includes a message unit which outputs a signal line separation message when the image forming device has no signal from the central service station or the communication control unit over a predetermined period.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of and claims the benefit of priorityunder 35 U.S.C. §120 from U.S. Ser. No. 09/195,604, filed Nov. 19, 1998,and claims the benefit of priority under 35 U.S.C. §119 from thefollowing Japanese Patent Applications: 9-322840, filed in Japan Nov.25, 1997, 9-328843, filed in Japan Nov. 28, 1997, 9-328842, filed inJapan Nov. 28, 1997, 9-328837, filed in Japan Nov. 28, 1997, 9-328789,filed in Japan Nov. 28, 1997, 10-065787, filed in Japan Mar. 16, 1998,and 10-251670, filed in Japan Sep. 4, 1998. Each of the aboveapplications is incorporated herein by reference.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to an image forming device managementsystem in which a plurality of image forming devices, such as copiers,facsimiles, or printers, are linked through a communication device to acentral service station, and each image forming device can automaticallytransmit a message to the central service station while the imageforming devices can be remotely controlled by the central servicestation

(2) Description of the Related Art

As disclosed in Japanese Laid-Open Patent Application Nos. 8-116399,6-329298 and 8-331355, there is known an image forming device managementsystem in which a plurality of image forming devices are linked througha communication device to a central service station. Japanese Laid-OpenPatent Application No. 8-116399 discloses a system in which a pluralityof image forming devices connected to a communication control unit via asignal line, located on a user site, are linked to a central servicestation at a remote location through a communication network.

In the system of the above publication, when the signal line between theimage forming device and the communication control unit is in adisconnected state, the central service station is unable to communicatewith the image forming device. Hence, as the central service station isunable to detect whether the image forming device is in a disconnectedstate, it is difficult for the central service station to speedilyprovide a maintenance service for the image forming device during itsdisconnected state.

Japanese Laid-Open Patent Application No. 6-329298 discloses an imageforming device maintenance system in which, when a jam of an imageforming device (or a copier) occurs, a determination as to whether thecopier requires a maintenance service is made on the side of the copierbased on its troubled condition. If it is determined that themaintenance service is required, the copier automatically transmits aservice request to a central service station via a communication device.According to the system of the above publication, when the servicerequest from the copier is received by the central service station, itis possible to have a serviceman speedily visit the user site andproperly recover the troubled condition of the copier.

In the system of the above publication, every time the determinationthat the maintenance service of the copier is required is made, theservice request is automatically transmitted from the copier to thecentral service station. For example, when a jam of the copierfrequently occurs, the automatic service request transmission andreceiving must be repeated many times by the system of the abovepublication. Hence, the system of the above publication is likely to bein a situation that the automatic service request transmission andreceiving is performed too many times although it is not necessary.

Japanese Laid-Open Patent Application No. 8-331355 discloses a method ofautomatically transmitting a maintenance service start message and amaintenance service end message from an image forming device on a usersite to a central service station at a remote location when amaintenance service of the image forming device on the user site isinitiated and terminated by a serviceman.

However, it is difficult for the method of the above publication tocarry out an automatic message transmission of the image forming devicein an appropriate situation during the maintenance operation of theimage forming device by the serviceman.

In addition to the maintenance service start/end messages, there areother messages which should be automatically transmitted to the centralservice station even during the maintenance service of the image formingdevice (or the copier). For example, when a lack of replenishment parts,such as toner, occurs, it is desirable to automatically transmit areplenishment part supply request from the copier to the central servicestation even during the maintenance service of the copier. Further,there are further messages which should not be automatically transmittedto the central service station during the maintenance service of thecopier. For example, when a certain error of the copier occurs after thestart of the maintenance service of the copier, it is undesirable toautomatically transit its error message from the copier to the centralservice station because the serviceman has already visited the usersite. Hence, there is a demand for an image forming device maintenancesystem which starts an automatic message transmission only in anappropriate situation when a maintenance operation of the copier isperformed by a serviceman.

Further, statistical data of the copier related to its troubledcondition may be changed during a maintenance service by a serviceman,and it is necessary to reset the statistical data of the copier at theend of the maintenance service. If it is not reset, the copier mayerroneously transmit an error message to the central service station,because of the changed data, after the maintenance service of thecopier.

Further, as disclosed in Japanese Laid-Open Patent Application No.5-276260, there is known a facsimile management system in which afacsimile is linked to a central service station (or a communicationterminal), and the central service station can write information to orread information from operating parameters retained in an internalmemory of the facsimile. When accessing the internal memory of thefacsimile, it is necessary to designate an absolute address of theinternal memory at which an operating parameter is retained.

Similar to the facsimile management system of the above type, there isknown an image forming device management system in which a plurality ofimage forming devices, such as copiers, connected to a communicationdevice on a user site, such as a customer office, are linked through apublic switched network to a central service station at a remotelocation, such as a sales or service location.

The above-described image forming device management system is intendedto efficiently and speedily provide a service for the image formingdevices by carrying out (1) a communication control of the centralservice station to the image forming devices, (2) a communicationcontrol of each of the image forming devices to the central servicestation, and (3) a control of the communication device by itself.

Further, there is known an image forming device management system havinga block billing function. The block billing function is provided for theimage forming device management system to establish a charge for apredetermined number of copy sheets as a contract for use of an imageforming device.

However, it is difficult for the above-described image forming devicemanagement to provide an efficient operation of the block billingfunction or a precise management of the image forming devices. It isdifficult to provide an easy-to-use image forming device managementsystem for the user.

For example, there are various kinds of image forming devices which areconnected to an image forming device management system having a blockbilling function. An address of the memory of each of the image formingdevices for retaining an operating parameter is different from oneanother if the image forming devices are of different models or ofdifferent versions.

In the image forming device management system, such as that of JapaneseLaid-Open Patent Application No. 5-276260 mentioned above, it isnecessary to designate an absolute address of the memory of one imageforming device (at which an operating parameter is retained) whenaccessing the memory of the image forming device. However, if the imageforming devices connected to the system are of different kinds, then itis necessary to deal with individual absolute addresses of the memoryfor each of different kinds of image forming devices. In this case, themanagement method for such image forming devices will be considerablycomplicated. This makes it difficult to take actions to upgrade theimage forming device management system.

Further, there is known an image forming device management system inwhich a maintenance service start message and a maintenance service endmessage are transmitted from an image forming device to a centralservice station when a message transmit operation is manually performedby a serviceman at the start and the end of the maintenance service ofthe image forming device. In the above-described system, the messagetransmission control is carried out when a service program, stored inthe image forming device, is executed.

However, if the serviceman fails to perform the message transmitoperation, the central service station does not receive the maintenanceservice start/end messages. In such a case, the central service stationdoes not recognize a time the maintenance service of the image formingdevice is initiated or terminated by the serviceman. Hence, it is likelythat the above-described system cannot provide a precise management ofthe image forming devices.

SUMMARY OF THE INVENTION

A first object of the present invention is to provide an image formingdevice management system which speedily provides a maintenance messagefor a user of one of image forming devices when a separation of a signalline between a communication control unit and the image forming deviceis detected.

A second object of the present invention is to provide an image formingdevice management system which effectively inhibits an automatic messagetransmission from one of a plurality of image forming devices to acentral service station when a jam of the image forming device or thelike occurs.

A third object of the present invention is to provide an image formingdevice management system which starts an automatic message transmissiononly in an appropriate situation when a maintenance service of an imageforming device is performed by a serviceman.

A fourth object of the present invention is to provide an image formingdevice management system which efficiently carries out a block billingfunction.

A fifth object of the present invention is to provide an image formingdevice management system which provides a precise management of imageforming devices by performing a block billing function in a simplemanner.

A sixth object of the present invention is to provide an image formingdevice management system which provides an easy-to-use managementoperation for the user.

A seventh object of the present invention is to provide an image formingdevice management system which provides a simple management scheme for acentral service station and need not deal with individual absoluteaddresses of the memory for each of different kinds of image formingdevices.

An eighth object of the present invention is to provide an image formingdevice management system which is able to manage an accurate time of astart or an end of a maintenance service of each of image formingdevices.

The above-mentioned first object of the present invention is achieved byan image forming device management system which includes a plurality ofimage forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationcontrol unit which is connected to each of the image forming devices bya signal line, the communication control unit connecting one of theimage forming devices to the central service station via a communicationnetwork, wherein each of the image forming devices includes a messageunit which outputs a signal line separation message when the imageforming device has no signal from the central service station or thecommunication control unit over a predetermined period.

According to the present invention, when the image forming device ofconcern does not receive a signal from the central service station orthe communication control unit over the predetermined period, the imageforming device outputs the signal line separation message. This allowsthe user of the image forming device to recognize a separation of thesignal line between the image forming device and the communicationcontrol unit. Hence, it is possible for the image forming devicemanagement system of the present invention to speedily provide amaintenance message for the user of the image forming device when aseparation of a signal line between the image forming device and thecommunication control unit occurs.

The above-mentioned second object of the present invention is achievedby an image forming device management system which includes a pluralityof image forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationcontrol unit connected to each of the image forming devices, thecommunication control unit connecting one of the image forming devicesto the central service station via a communication network, wherein eachof the image forming devices includes: a jam detection unit whichdetects a jam of the image forming device; an image formation detectionunit which detects a normal end of image formation by the image formingdevice; a remote message unit which transmits a first remote messagethrough the communication control unit to the central service station,the first remote message indicating that the jam of the image formingdevice is continuously detected for a predetermined number of copysheets before the normal end of image formation by the image formingdevice is detected; and a remote message inhibition unit which inhibitsthe remote message unit from transmitting a subsequent remote messageafter the transmission of the first remote message until the normal endof image formation by the image forming device is detected.

According to the present invention, the remote message inhibition unitinhibits the automatic message transmission until the normal end ofimage formation is detected. It is possible to effectively inhibits theautomatic message transmission from the image forming device to thecentral service station when a jam of the image forming device occurs.

The above-mentioned second object of the present invention is achievedby an image forming device management system which includes a pluralityof image forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationcontrol unit connected to each of the image forming devices, thecommunication control unit connecting one of the image forming devicesto the central service station via a communication network, wherein eachof the image forming devices includes: a jam detection unit whichdetects a jam of the image forming device; an image formation detectionunit which detects a normal end of image formation by the image formingdevice; a remote message unit which transmits a remote message throughthe communication control unit to the central service station, theremote message indicating that the jam of the image forming device iscontinuously detected for a predetermined number of copy sheets beforethe normal end of image formation by the image forming device isdetected; a time counter which outputs a time count indicating a periodof the jam of the image forming device; and a remote message inhibitionunit which inhibits the remote message unit from transmitting the remotemessage when the time count output by the time counter exceeds apredetermined value.

According to the present invention, the remote message inhibition unitinhibits the automatic message transmission when the time count outputby the time counter exceeds a predetermined value. It is possible toeffectively inhibits the automatic message transmission from the imageforming device to the central service station when a jam of the imageforming device occurs.

The above-mentioned third object of the present invention is achieved byan image forming device management system which includes a plurality ofimage forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationdevice which connects one of the image forming devices to the centralservice station via a communication network, wherein each of the imageforming devices includes: a remote message unit which transmits a remotemessage through the communication device to the central service stationwhen a maintenance service of the image forming device is initiated orterminated by a serviceman; and a non-volatile memory which retains acontent of a serviceman visit flag, the serviceman visit flag indicatingwhether the maintenance service of the image forming device is initiatedor terminated by the serviceman.

According to the present invention, each of the image forming devices inthe image forming device management system includes the non-volatilememory which retains the content of the serviceman visit flag, theserviceman visit flag indicating whether the maintenance service of theimage forming device is initiated or terminated by the serviceman. Byusing the non-volatile memory, it is possible to start an automaticmessage transmission only in an appropriate situation when a maintenanceservice of an image forming device is performed by a serviceman.

The above-mentioned fourth object of the present invention is achievedby an image forming device management system which includes a pluralityof image. forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationdevice which connects one of the image forming devices to the centralservice station via a communication network, wherein each of the imageforming devices includes: a receiving unit which receives anon-resettable copy count and a remote message cycle, both transmittedto the image forming device by the central service station through thecommunication device, the copy count indicating a predetermined numberof copy sheets with respect to a contract for use of the image formingdevice, the remote message cycle indicating a frequency at which theimage forming device transmits a remote message to the central servicestation; a first storage unit which stores the copy count and the remotemessage cycle received by the receiving unit; a second storage unitwhich stores a current copy count that is incremented every time animage formation of one copy sheet is performed by the image formingdevice; a control unit which sets the image forming device in a remotemessage enable state when a difference between the current copy countand the received copy count reaches an integral multiple of the remotemessage cycle; and a remote message unit which transmits the remotemessage through the communication device to the central service stationafter the image forming device is set in the remote message enable stateby the control unit.

According to the present invention, the image forming device of concernis set in the remote message enable state when the difference betweenthe current copy count and the received copy count reaches an integralmultiple of the remote message cycle. The remote message unit transmitsthe remote message to the central service station after the imageforming device is set in the remote message enable state. It is possiblefor the image forming device management system of the present inventionto efficiently carry out a block billing function.

The above-mentioned fifth object of the present invention is achieved byan image forming device management system which includes a plurality ofimage forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationdevice which connects one of the image forming devices to the centralservice station via a communication network, wherein each of the imageforming devices includes: a receiving unit which receives anon-resettable copy count and a remote message cycle, both transmittedto the image forming device by the central service station through thecommunication device, the copy count indicating a predetermined numberof copy sheets with respect to a contract for use of the image formingdevice, the remote message cycle indicating a frequency at which theimage forming device transmits a remote message to the central servicestation; a first storage unit which stores the copy count and the remotemessage cycle received by the receiving unit; a second storage unitwhich stores a current copy count that is incremented every time animage formation of one copy sheet is performed by the image formingdevice; a control unit which sets the image forming device in a remotemessage enable state when a difference between the current copy countand the received copy count reaches an integral multiple of the remotemessage cycle; and a remote message unit which transmits the remotemessage through the communication device to the central service stationafter the image forming device is set in the remote message enable stateby the control unit, and wherein the remote message transmitted to thecentral service station by the remote message unit includes a remotemessage purpose and the current copy count.

It is possible for the image forming device management system of thepresent invention to provide a precise management of the image formingdevices by performing a block billing function in a simple manner.

The above-mentioned sixth object of the present invention is achieved byan image forming device management system which includes a plurality ofimage forming devices, each of the image forming devices havingoperating parameters stored in a memory of the image forming device, andabsolute addresses of the memory where the respective operatingparameters are stored being predetermined according to a kind of eachoperating parameter, a central service station which reads informationfrom or writes information to the operating parameters of one of theimage forming devices by transmitting an access request to said one ofthe image forming devices, and a communication device which connects oneof the image forming devices to the central service station via acommunication network, wherein the central service station includes: aparameter code transmitting unit which transmits a parameter code,indicating a kind of a particular one of the operating parameters,through the communication device to one of the image forming deviceswhen transmitting an access request to said one of the image formingdevices, and wherein each of the image forming devices includes: anaddress determination unit responsive to the access request whichdetermines a particular absolute address of the memory of the imageforming device in accordance with the parameter code transmitted by thecode transmitting unit; and an access request processing unit whichaccesses the particular one of the operating parameters at the absoluteaddress of the memory determined by the address determination unit.

According to the present invention, each of the image forming devices inthe image forming device management system has the absolute addresses ofthe memory where the respective operating parameters are stored whichare predetermined according to the kind of each operating parameter. Theaccess request processing unit accesses one of the operating parametersat an absolute address of the memory determined by the addressdetermination unit. It is possible to avoid dealing with individualabsolute addresses of the memory for each of different kinds of imageforming devices. It is possible to provide an easy-to-use managementoperation for the user.

The above-mentioned seventh object of the present invention is achievedby an image forming device management system which includes a pluralityof image forming devices, each of the image forming devices havingoperating parameters stored in a memory of the image forming device, andabsolute addresses of the memory where the respective operatingparameters are stored being predetermined according to a kind of eachoperating parameter, a central service station which reads informationfrom or writes information to the operating parameters of one of theimage forming devices by transmitting an access request to said one ofthe image forming devices, and a communication device which connects oneof the image forming devices to the central service station via acommunication network, wherein the central service station includes: aparameter code transmitting unit which transmits a parameter code,indicating a kind of a particular one of the operating parameters,through the communication device to one of the image forming deviceswhen transmitting an access request to said one of the image formingdevices, and wherein each of the image forming devices includes: anaddress determination unit responsive to the access request whichdetermines a particular absolute address of the memory of the imageforming device in accordance with the parameter code transmitted by thecode transmitting unit; and an access request processing unit whichaccesses the particular one of the operating parameters at the absoluteaddress of the memory determined by the address determination unit, andwherein the image forming devices are of different models and share acommon parameter code indicating an identical kind for the operatingparameters of the individual image forming devices regardless of themodel of each image forming device.

According to the above-described image forming device management system,it is possible to provide a simple management scheme for the centralservice station and need not deal with individual absolute addresses ofthe memory for each of different kinds of image forming devices.

The above-mentioned eighth object of the present invention is achievedby an image forming device management system which includes a pluralityof image forming devices, a central service station which provides amaintenance service for the image forming devices, and a communicationdevice which connects one of the image forming devices to the centralservice station via a communication network, wherein each of the imageforming devices includes: a first request unit which outputs a modeshift request to the image forming device, the mode shift requestinitiating a shift of the image forming device to a maintenance mode; amaintenance mode start unit which sets the image forming device in themaintenance mode in response to the mode shift request output by thefirst request unit; a first remote message unit which transmits a firstremote message through the communication device to the central servicestation in response to the mode shift request output by the firstrequest means, the first remote message indicating a start of amaintenance service of the image forming device; a second request unitwhich outputs a maintenance end request to the image forming device, themaintenance end request terminating the maintenance mode of the imageforming device; and a second remote message unit which transmits asecond remote message through the communication device to the centralservice station in response to the maintenance end request output by thesecond request unit, the second remote message indicating an end of themaintenance service of the image forming device.

Further, the above-mentioned eighth object of the present invention isachieved by an image forming device management system which includes aplurality of image forming devices, a central service station whichprovides a maintenance service for the image forming devices, and acommunication device which connects one of the image forming devices tothe central service station via a communication network, wherein each ofthe image forming devices includes: a first request unit which outputs amode shift request to the image forming device, a first display unitwhich displays a first mode shift key in response to the mode shiftrequest output by the first request unit, a second request unit whichinitiates a shift of the image forming device to a maintenance mode whenthe first mode shift key displayed by the first display unit is turnedON; a maintenance mode start unit which sets the image forming device inthe maintenance mode when the shift of the image forming device to themaintenance mode is initiated by the second request unit; a first remotemessage unit which transmits a first remote message through thecommunication device to the central service station when the shift ofthe image forming device to the maintenance mode is initiated by thesecond request unit, the first remote message indicating a start of amaintenance service of the image forming device; a third request unitwhich outputs a maintenance end request to the image forming device, themaintenance end request terminating the maintenance mode of the imageforming device; and a second remote message unit which transmits asecond remote message through the communication device to the centralservice station in response to the maintenance end request output by thesecond request unit, the second remote message indicating an end of themaintenance service of the image forming device.

It is possible for the above-described image forming device managementsystem to manage an accurate time of the start or the end of themaintenance service of each of image forming devices by the serviceman.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will bemore apparent from the following detailed description when read inconjunction with the accompanying drawings in which:

FIG. 1 is a block diagram of one embodiment of an image forming devicemanagement system of the present invention;

FIG. 2 is a block diagram of a control part of a copier in the imageforming device management system of FIG. 1;

FIG. 3 is a block diagram of a communication control unit CCU in theimage forming device management system of FIG. 1;

FIG. 4 is a block diagram of a central service station CSS in the imageforming device management system of FIG. 1;

FIG. 5 is a diagram for explaining a communication sequence of a remotemessage transmission when a remote message key is turned ON;

FIG. 6 is a diagram for explaining a communication sequence of a remotemessage transmission when a self-diagnostic error takes place;

FIG. 7 is a diagram for explaining a communication sequence of a remotemessage transmission when an advance warning remote message istransmitted;

FIG. 8A, FIG. 8B and FIG. 8C are diagrams for explaining respectivecommunication sequences when a read request, a write request and anexecute request are transmitted to the copier by the CSS;

FIG. 9A, FIG. 9B and FIG. 9C are diagrams for explaining respectivecommunication sequences when a read request, a write request and anexecute request are transmitted to the CCU by the CSS;

FIG. 10 is a diagram for explaining a communication sequence when a readrequest is transmitted to the copier by the CCU;

FIG. 11 is a diagram for explaining various parameters which are set inthe CCU;

FIG. 12A, FIG. 12B and FIG. 12C are diagrams for explaining data formatsof messages when a remote message transmission is performed;

FIG. 13A, FIG. 13B and FIG. 13C are diagrams for explaining data formatsof messages when a request is transmitted to the copier by the CSS;

FIG. 14A, FIG. 14B and FIG. 14C are diagrams for explaining data formatsof messages when a request is transmitted to the CCU by the CSS;

FIG. 15A and FIG. 15B are diagrams for explaining data formats ofmessages when a request is transmitted to the copier by the CCU;

FIG. 16 is a flowchart for explaining a remote message transmissionprocess performed by a control unit of the copier;

FIG. 17 is a flowchart for explaining a remote message key transmissionsub-process in the remote message transmission process of FIG. 16;

FIG. 18 is a flowchart for explaining a self-diagnostic error remotemessage sub-process in the remote message transmission process of FIG.16;

FIG. 19 is a flowchart for explaining an advance warning remote messagesub-process in the remote message transmission process of FIG. 16;

FIG. 20 is a flowchart for explaining a remote message transmissionprocess performed by the control unit of the copier when a request istransmitted to the copier by the CCU;

FIG. 21 is a flowchart for explaining a read sub-process in the remotemessage transmission process of FIG. 20;

FIG. 22 is a flowchart for explaining a write sub-process in the remotemessage transmission process of FIG. 20;

FIG. 23 is a flowchart for explaining an execute sub-process in theremote message transmission process of FIG. 20;

FIG. 24 is a diagram for explaining a communication sequence of the CCUand the copier during an idle condition;

FIG. 25 is a diagram for explaining a communication sequence of the CCUand the copier during a remote message transmission;

FIG. 26 is a diagram for explaining a communication sequence of the CCUand the copier during a remote message receiving;

FIG. 27 is a diagram for explaining a communication sequence of the CCUand the copier when an access request is transmitted to the copier;

FIG. 28 is a flowchart for explaining a signal line separation messageprocess performed by the copier in a first embodiment of the imageforming device management system;

FIG. 29 is a flowchart for explaining a no-communication counterresetting process performed by the copier in the first embodiment;

FIG. 30 is a diagram for explaining a communication sequence of the CCUand the copier when the signal line separation message process utilizesa selecting of the CCU to the copier;

FIG. 31 is a diagram for explaining a communication sequence of the CSSand the copier when the signal line separation message process utilizesa selecting of the CSS to the copier;

FIG. 32 is a diagram for explaining a communication sequence of the CCUand the copier when the signal line separation message process utilizesa polling of the CCU to the copier;

FIG. 33 is a diagram for explaining a signal line separation messageprocess utilizing a detection of a voltage of a terminal of acommunication interface unit of the copier;

FIG. 34 is a flowchart for explaining a signal line separation messageprocess performed by the copier using a detected voltage of the terminalof the communication interface unit;

FIG. 35A and FIG. 35B are diagrams for explaining a signal lineseparation message process utilizing a connect detection line betweenthe CCU and the copier;

FIG. 36 is a flowchart for explaining a signal line separation messageprocess performed by the copier using a connect detection line betweenthe CCU and the copier;

FIG. 37 is a flowchart for explaining a first jam detection processperformed by the copier in a second embodiment of the image formingdevice management system;

FIG. 38 is a flowchart for explaining a second jam detection processperformed by the copier in the second embodiment;

FIG. 39 is a flowchart for explaining another second jam detectionprocess performed by the copier in the second embodiment;

FIG. 40 is a flowchart for explaining a CSS function setting processperformed by the copier in the second embodiment;

FIG. 41 is a flowchart for explaining a maintenance service start/endmessage process performed by the copier in a third embodiment of theimage forming device management system;

FIG. 42 is a flowchart for explaining another maintenance servicestart/end message process performed by the copier in the thirdembodiment;

FIG. 43 is a flowchart for explaining a further maintenance servicestart/end message process performed by the copier in the thirdembodiment;

FIG. 44 is a block diagram of a fourth embodiment of the image formingdevice management system of the present invention;

FIG. 45 is a block diagram of a data communication device DCD in thefourth embodiment of the image forming device management system;

FIG. 46 is a flowchart for explaining a selecting process performed to aparticular one of the image forming devices by the DCD in the fourthembodiment;

FIG. 47 is a flowchart for explaining a polling process performed to theimage forming devices by the DCD in the fourth embodiment;

FIG. 48 is a block diagram of a control part of an image forming devicein the fourth embodiment;

FIG. 49 is a block diagram of a personal interface PI in the controlpart of the image forming device in the fourth embodiment;

FIG. 50 is a schematic diagram of a control panel of the image formingdevice in the fourth embodiment;

FIG. 51 is a schematic diagram of a character display part in thecontrol panel of the image forming device of FIG. 50;

FIG. 52 is a diagram for explaining a data format of a messagetransmitted between the CSS and the DCD in the fourth embodiment;

FIG. 53 is a diagram for explaining a data format of a messagetransmitted between the DCD and the PI in the fourth embodiment;

FIG. 54 is a diagram for explaining a data format of a messagetransmitted between the PI and the image forming device in the fourthembodiment;

FIG. 55 is a diagram for explaining a data format of the messagetransmitted between the PI and the image forming device in the fourthembodiment;

FIG. 56 is a flowchart for explaining a block billing process performedby the image forming device in the fourth embodiment;

FIG. 57 is a diagram for explaining a data format of a messagetransmitted between the PI and the image forming device during the blockbilling process;

FIG. 58 is a diagram for explaining another data format of the messagetransmitted between the PI and the image forming device during the blockbilling process;

FIG. 59 is a schematic diagram of a user-program mode indicationdisplayed on the character display part in the control panel of theimage forming device;

FIG. 60 is a block diagram of a fifth embodiment of the image formingdevice management system of the present invention;

FIG. 61 is a diagram for explaining a parameter code stored in a ROM ofan image forming device in the fifth embodiment;

FIG. 62A and FIG. 62B are diagrams for explaining respectivecommunication sequences when a read request and a write request aretransmitted to the image forming device by the CSS;

FIG. 63 is a flowchart for explaining a main control process performedby a control part of the image forming device when an access request istransmitted to the image forming device by the CSS;

FIG. 64 is a flowchart for explaining a read sub-process in the maincontrol process of FIG. 63;

FIG. 65 is a flowchart for explaining a write sub-process in the maincontrol process of FIG. 63;

FIG. 66 is a schematic diagram of a control panel of the image formingdevice in the sixth embodiment;

FIG. 67 is a schematic diagram of an image formation mode indicationdisplayed on a character display part of the control panel of the imageforming device of FIG. 66;

FIG. 68 is a schematic diagram of a service program mode indicationdisplayed on the character display part of the control panel of theimage forming device of FIG. 66;

FIG. 69 is a flowchart for explaining a maintenance service startmessage process performed by the image forming device in the sixthembodiment when a mode shift request is output;

FIG. 70 is a flowchart for explaining a maintenance service end messageprocess performed by the image forming device in the sixth embodiment;

FIG. 71 is a schematic diagram of a maintenance service start messagekey displayed on the character display part of the control panel of theimage forming device of FIG. 66;

FIG. 72 is a flowchart for explaining a maintenance service startmessage process performed by the image forming device in the sixthembodiment when a mode shift request is output;

FIG. 73 is a flowchart for explaining a maintenance service end messageprocess performed by the image forming device in the sixth embodiment;and

FIG. 74A and FIG. 74B are diagrams for explaining data formats of amaintenance service start message and a maintenance service end messagetransmitted to the CSS by the image forming device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A description will now be given of the preferred embodiments of thepresent invention with reference to the accompanying drawings.

1. First Embodiment

1.1 Structure of System

FIG. 1 shows a first embodiment of the image forming device managementsystem of the present invention. As shown in FIG. 1, in the imageforming device management system of the first embodiment, a plurality ofimage forming devices 100, such as plain paper copiers PPC (shown inFIG. 1) or printers (not shown in FIG. 1), are provided on each of auser site US1 and a user site US2. It is a matter of course that theimage forming device management system of the present invention mayinclude only one image forming device. Hence, the image forming devicemanagement system may include one or more image forming devices 100provided therein. For the sake of convenience, one of the image formingdevices 100 in the following description will be called the copier 100,unless otherwise specified.

In the image forming device management system of FIG. 1, a communicationcontrol unit CCU 200 is also provided on each of the user sites US1 andUS2, and the plurality of image forming devices 100 of each user siteare connected to the CCU 200. The CCU 200 of each user site is linked toa central service station CSS 300 at a remote location via a publicswitched network PSN 250. In the embodiment of FIG. 1, a telephone set206 a is connected to the CCU 200 of the user site US1, and a facsimile206 b is connected to the CCU 200 of the user site US2.

The CCU 200 in the first embodiment is, for example, a communicationcontrol device that is capable of being connected up to five imageforming devices, and the interface between each image forming device 100and the CCU 200 is provided by a multidrop connection which is inconformity with RS-485 standard. The communication sequence between eachimage forming device 100 and the CCU 200 is performed in accordance withbasic data transmission procedures. The CCU 200 can communicate with oneof the image forming devices 100 after a data link between the CCU 200and the image forming device 100 is established by using a centralizedpolling/selecting control method. A specific device address can be setfor each of the image forming devices 100 by setting an address settingswitch (for example, the element 1031 in FIG. 2) of each image formingdevice 100, and a polling address and a selecting address can be set foreach image forming device 100 in accordance with the specific deviceaddress.

1.2 Structure of Image Forming Device

1.2.1 Mechanical Structure

The copier 100 in the first embodiment is an analog-type image formingdevice in which an electrostatic latent image is formed on aphotosensitive drum when an original image is optically read by ascanner. In the copier 100, a charger unit, a discharger unit, adeveloping unit, a transfer unit, a pre-transfer charger unit, acleaning unit and a fixing unit, which are required to perform anelectrophotographic process, are provided around the periphery of thephotosensitive drum. Further, in the copier 100, a sheet supplyingdevice and a sheet transporting device are provided. Such structure ofthe copier 100 is known in the prior art, and a detailed descriptionthereof will be omitted.

In a control panel (not shown) of the copier 100, various keys, displaysand controls are provided, including a timer key, a timer indicator, aprogram key, an ENTER key, ten keys, a guidance key, a guidanceindicator, a sizing key, a sizing indicator, a centering key, acentering indicator, a paper offset key, a paper offset indicator, aboth side indicator, a remote message key, and a remote messageindicator. The remote message key and the remote message indicator arerelated to the present invention and provided within the copier 100. Theremote message key and the remote message indicator will be describedlater. Further, in the control panel of the copier 100, a duplex copykey, a page copy indicator, a page copy indicator, a delete key, adelete indicator, a sheet-designated sizing key, a sheet-designatedsizing indicator, a zoom key, a reduce key, an enlarge key, a normalsize key, a sheet select key, an auto sheet select key, a density adjustkey, an auto density set key, a clear/stop key, a start key, aninterrupt key, a preheat indicator, a mode-clear/preheat key, and etc.

1.2.2 Electrical Structure

FIG. 2 shows a control part of one of the copiers 100 in the imageforming device management system of the first embodiment. As shown inFIG. 2, the copier 100 is controlled by a CPU (central processing unit)1001. A control program executed by the CPU 1001 and control data usedfor controlling the copier 100 are stored in a ROM (read-only memory)1002. A RAM (random access memory) 1003 provides a working storage areafor the CPU 1001 when executing the control program. A communicationinterface unit 1004 provides an interface between the copier 100 and theCCU 200 when the copier 100 transmits data to the CCU 200 and receivescontrol data and control codes from the CCU 200.

In the copier 100 of FIG. 2, an A/D (analog-to-digital) converter 1005converts various operating voltages of various sensors 1006 of thecopier 100 into digital signals, and the digital signals are supplied tothe CPU 1001. A lamp voltage of the scanner, a light emission voltageand a light receiving voltage of a P sensor (provided for adjusting atoner density), an output of an ADS (auto density setting) sensor, anoutput of a light amount sensor, an output of a current sensor of thephotosensitive drum, and a voltage of a fixing unit thermistor aresupplied to an input of the A/D converter 1005. In the copier 100 ofFIG. 2, when a fixing temperature indicated by the voltage of the fixingunit thermistor is below a given temperature, a copying operation of thecopier 100 is inhibited.

In the copier 100 of FIG. 2, an operation part 1010 includes theabove-described keys of the control panel. The above-mentioned remotemessage key is provided within the operation part 1010 of the copier100. The CPU 1001 reads out the settings of the operation part 1010 whena power switch is turned ON. A remote message enable switch 1032 isprovided in the copier 100, and the remote message enable switch 1032 isconnected to the CPU 1001. When the remote message enable switch 1032 isturned ON during the ON state of the power switch, the CPU 1001 allowsthe copier 100 to perform a remote message transmission with respect tothe CSS 300. When the remote message enable switch 1032 is turned OFF,the CPU 1001 inhibits the copier 100 from performing the remote messagetransmission. Further, the CPU 1001 outputs a control signal to each ofthe above-described indicators of the control panel.

In the copier 100 of FIG. 2, an optical system control unit 1011 isconnected to the CPU 1001, and the optical system control unit 1011controls an exposure lamp 1012 of the scanner. A high-voltage supplyunit 1013 is connected to the CPU 1001, and the high-voltage supply unit1013 supplies a high voltage to each of load resistors of variouselements 1014 including the charger unit, the discharger unit, thetransfer charger unit, the developing unit, and the PTC (pre-transfercharger) unit. A motor control unit 1015 is connected to the CPU 1001,and the motor control unit 1015 controls a main motor 1016. A heatercontrol unit 1017 is connected to the CPU 1001, and the heater controlunit 1017 controls a fixing heater 1018 of the fixing unit. A sensorcontrol unit 1021 is connected to the CPU 1001, and the sensor controlunit 1021 controls various sensors 1022. Specifically, the sensorcontrol unit 1021 controls a light receiving gain of each of the lightamount sensor, the ADS sensor and the P sensor, and controls a lightemission voltage of the P sensor.

1.3 Communication Control Unit

FIG. 3 shows the CCU 200 in the image forming device management systemof the first embodiment. As shown in FIG. 3, the CCU 200 is controlledby a CPU 201 similar to the copier 100. A control program executed bythe CPU 201 and control data used for controlling the CCU 200 are storedin a ROM 202. A RAM 203 provides a working storage area for the CPU 201when executing the control program. A battery 203 a is connected to theRAM 203, and the battery 203 a serves to allow the RAM 203 to retainintermediate results of the execution of the control program even aftera power switch is turned OFF.

Further, in the CCU 200 of FIG. 3, a switching device 207 is connectedto the CPU 201, and the switching device 207 selects one of a connectionof the telephone set 206 a (or the facsimile 206 b) and the PSN 250 anda connection of the CCU 200 and the PSN 250. Either the telephone set206 a or the facsimile 206 b may be connected through the switchingdevice 207 to the CCU 200. A modem 204 is connected to the CPU 201 andthe switching device 207, and the model 204 provides a communicationinterface between the CCU 200 and the PSN 250 when the copier 100transmits data to the CSS 300 via the PSN 250 and receives control dataand control codes from the CSS 300 via the PSN 250. An RS-485 interfaceunit 205 provides the data transmission interface between the copier 100and the CCU 200 which is in conformity with RS-485 standard. Further, inthe CCU 200 of FIG. 3, a total counter value transmission enable switch208 and a clock 209 are provided.

The CCU 200 receives data supplied by the copier 100, and transmits thedata through the PSN 250 to the CSS 300. Further, the CCU 200 receivescontrol codes and control data supplied by the CSS 300, and transmitsthem to the copier 100. The CCU 200 sends a control signal to thehigh-voltage supply unit 1013 of the copier 100 so as to control theON/OFF of the power switch of the copier 100. The CCU 200 recognizes theidentification of each of the copiers 100 which are connected the CCU200 within the same user site. The CCU 200 deals with the remote messagetransmission of each of the copiers 100 connected to the CCU 200 withinthe same user site. The switching device 207 in the CCU 200 selects oneof the connection of the telephone set 206 a (or the facsimile 206b) andthe PSN 250 and the connection of the CCU 200 and the PSN 250.

1.4 Central Service Station

FIG. 4 shows the CSS 300 in the image forming device management systemof the first embodiment. As shown in FIG. 4, the CSS 300 includes a hostcomputer 301 which performs various management processes. A storagedevice 302 is connected to the host computer 301, and stores managementdata which is used by the host computer 301 when performing themanagement processes. A modem 303 is connected to the host computer 301,and provides a communication interface between the host computer 301 andthe PSN 250 when the copier 100 transmits data to the CSS 300 via thePSN 250 and receives control data and control codes from the CSS 300 viathe PSN 250. Further, in the CSS 300 of FIG. 4, a display monitor 304, akeyboard 305 and a printer 306 are provided.

1.5 Communication Sequences

FIG. 5 shows a communication sequence of the remote message transmissionwhen the remote message key is turned ON. When the remote message key,provided in the operation part 1010 of the copier 100, is turned ON, thecopier 100 transmits a remote message key transmission message to theCCU 200, as shown in FIG. 5. The remote message key transmission messagesent by the copier 100 is received by the CCU 200, and the CCU 200originates a call to a predetermined telephone number of the CSS 300 viathe PSN 250. When a data link between the CCU 200 and the CSS 300 isestablished, the CCU 200 transmits a remote message key transmissionmessage to the CSS 300 via the PSN 250. The CSS 300 is usually installedat a service location remote from the user site. The message sent atthis time to the CSS 300 by the CCU 200 is one of various kinds ofmessages sent to the CSS 300 by the CCU 200, and includes only data ofpreset parameters of the CCU 200 contained in the remote message keytransmission message. The parameters of the CCU 200 can be set orrewritten by the CSS 300 through a data transmission from the CSS 300 tothe CCU 200 via the PSN 250.

When the transmission of the message from the CCU 200 to the CSS 300 isperformed, the CCU 200 transmits a transmission result to the copier 100which is the originating station, the transmission result indicating aresult of the transmission between the CCU 200 and the CSS 300. Byreceiving the transmission result sent by the CCU 200, the copier 100 isinformed as to whether the transmission of the message normally ends orabnormally ends.

The copier 100 generally has a self-diagnostic function. For example,when an error of the fixing temperature or an error of adjustmentcontrols in the copier 100 is detected as a result of theself-diagnostic testing, an error message or a serviceman call messageis displayed in the copier 100.

FIG. 6 shows a communication sequence of the remote message transmissionwhen a self-diagnostic error takes place. When a self-diagnostic (S/D)error is detected as a result of the S/D testing of the copier 100, thecopier 100 transmits an S/D error remote message to the CCU 200, asshown in FIG. 6. The S/D error remote message sent by the copier 100 isreceived by the CCU 200, and the CCU 200 originates a call to apredetermined telephone number of the CSS 300 via the PSN 250. When adata link between the CCU 200 and the CSS 300 is established, the CCU200 transmits an S/D error remote message to the CSS 300 via the PSN250. When the transmission of the message from the CCU 200 to the CSS300 is performed, the CCU 200 transmits a transmission result to thecopier 100 which is the originating station, the transmission resultindicating a result of the transmission between the CCU 200 and the CSS300. By receiving the transmission result sent by the CCU 200, thecopier 100 is informed as to whether the transmission of the messagenormally ends or abnormally ends.

The copier 100 generally has an advance warning function. For example,when no significant error is detected as a result of the self-diagnostictesting but the copier 100 determines that the copier 100 requires amaintenance service, an advance warning remote message is transmitted tothe CSS 300 by the copier 100.

FIG. 7 shows a communication sequence of the remote message transmissionwhen an advance warning remote message is transmitted. As shown in FIG.7, the copier 100 transmits an advance warning remote message to the CCU200. The advance warning remote message sent by the copier 100 isreceived by the CCU 200, and the CCU 200 originates a call to apredetermined telephone number of the CSS 300 via the PSN 250. When adata link between the CCU 200 and the CSS 300 is established, the CCU200 transmits an advance warning remote message to the CSS 300 via thePSN 250. The CCU 200 in this case does not transmit a transmissionresult to the copier 100 (or the originating station) when thetransmission of the message from the CCU 200 to the CSS 300 isperformed.

When the S/D error remote message is sent to the CCU 200, the copier 100in the first embodiment does not work. When the advance warning remotemessage is sent to the CCU 200, the copier 100 in the first embodimentis workable. Even during the transmission of the advance warning remotemessage, the copier 100 starts performing the copying operation if anoriginal document is placed on the copier 100 and the start key isturned ON. However, when the load on the control part of the copier 100will be excessively high if the copying operation is performed, thetransmission of the advance warning remote message may be interrupted.

Generally, the degree of emergency for the advance warning remotemessage is lower than that for the A/D error remote message. It ispossible to defer the transmission of the advance warning remote messagefrom the CCU 200 to the CSS 300 until the frequency of use of thetelephone set 206 a or the facsimile 206 b is kept at an adequately lowlevel or until the traffic of the PSN 250 is kept at an adequately lowlevel. The deferred time of the transmission of the message can be setby the CSS 300 through the communication between the CSS 300 and the CCU200 via the PSN 250.

FIG. 8A, FIG. 8B and FIG. 8C show respective communication sequenceswhen a read request, a write request and an execute request aretransmitted to the copier 100 by the CSS 300.

The communication sequence of FIG. 8A is performed when a read requestis transmitted to the copier 100 by the CSS 300. The read request isissued by the CSS 300 in order to read logging data of the copier 100,the settings of the parameters of the copier 100 or the outputs of thesensors of the copier 100. The communication sequence of FIG. 8B isperformed when a write request is transmitted to the copier 100 by theCSS 300. The write request is issued by the CSS 300 in order to transmitnew data from the CSS 300 to the copier 100 and write the new data tothe parameters of the copier 100. The communication sequence of FIG. 8Cis performed when an execute request is transmitted to the copier 100 bythe CSS 300. The execute request is issued by the CSS 300 in order tohave the copier 100 perform a testing operation.

In each of the communication sequences of FIG. 8A through FIG. 8C, theCSS 300 originates a call to a predetermined telephone number of the CCU200 via the PSN 250. When a data link between the CCU 200 and the CSS300 is established, the CSS 300 transmits a request to the CSS 300 viathe PSN 250. The request sent by the CSS 300 includes an identificationof a designation copier 100 to which the request is made by the CSS 300.When the request from the CSS 300 is received by the CCU 200, the CCU200 transmits the request to the designation copier 100. When therequest from the CCU 200 is received by the designation copier 100, thedesignation copier 100 processes the request and transmits a response tothe request to the CCU 200. When the response from the designationcopier 100 is received by the CCU 200, the CCU 200 transmits theresponse to the CSS 300 via the PSN 250. In this manner, thecommunication sequence for each request sent to the copier 100 by theCSS 300 is performed by the image forming device management system ofthe first embodiment.

FIG. 9A, FIG. 9B and FIG. 9C show respective communication sequenceswhen a read request, a write request and an execute request aretransmitted to the CCU 200 by the CSS 300.

The communication sequence of FIG. 9A is performed when a read requestis transmitted to the CCU 200 by the CSS 300. The read request is issuedby the CSS 300 in order to read the settings of the parameters of theCCU 200 or the status of the CCU 200. Alternatively, the read request isissued by the CSS 300 in order to read the internal data of the copier100 previously read by the CCU 200. The communication sequence of FIG.9B is performed when a write request is transmitted to the CCU 200 bythe CSS 300. The write request is issued by the CSS 300 in order totransmit new data from the CSS 300 to the CCU 200 and write the new datato the parameters of the CCU 200. The communication sequence of FIG. 9Cis performed when an execute request is transmitted to the CCU 200 bythe CSS 300. The execute request is issued by the CSS 300 in order tohave the CCU 200 perform a testing operation.

In each of the communication sequences of FIG. 9A through FIG. 9C, theCSS 300 originates a call to a predetermined telephone number of the CCU200 via the PSN 250. When a data link between the CCU 200 and the CSS300 is established, the CSS 300 transmits a request to the CSS 300 viathe PSN 250. When the request from the CSS 300 is received by the CCU200, the CCU 200 processes the request and transmits a response to therequest to the CSS 300. In this manner, the communication sequence foreach request sent to the CCU 200 by the CSS 300 is performed by theimage forming device management system of the first embodiment.

FIG. 10 shows a communication sequence when a read request istransmitted to the copier 100 by the CCU 200.

The communication sequence of FIG. 10 is performed when a read requestis transmitted to the copier 100 by the CCU 200. The read request isissued by the CCU 200 regardless of the CSS 300, in order to read thelogging data of the copier 100, the settings of the parameters of thecopier 100 or the outputs of the sensors of the copier 100. In thecommunication sequence of FIG. 10, the CCU 200 transmits a read requestto the copier 100. When the read request from the CCU 200 is received bythe copier 100, the copier 100 processes the request and transmits aresponse to the request to the CCU 200. In this manner, the data of thecopier 100 is read by the CCU 200. Further, the data of the copier 100previously read by the CCU 200 is read by the CSS 300 by performing thecommunication sequence of FIG. 9A.

FIG. 11 shows various parameters which are set in the CCU 200 in theimage forming device management system of the first embodiment. Supposethat device addresses 1 through 5 are assigned to the image formingdevices 100 (or the copiers 100) in the image forming device managementsystem of FIG. 1.

As shown in FIG. 11, the parameters, set in the CCU 200 are grouped intosix blocks, including an image forming device block, a remote messagekey transmission block, an S/D error remote message block, an advancewarning remote message block, a total counter value transmission block,and a telephone setting block. In the image forming device block, amodel number and a serial number are retained with respect to each ofthe respective copiers 100. When a message is transmitted from aparticular one of the copiers 100 to the CCU 200, the CCU 200 adds themodel number and serial number (or the parameters corresponding to thatcopier 100) to the message as the identification of that copier 100, andtransmits the message, including the identification of the copier 100,to the CSS 300. When an access request, including an identification of adestination copier 100, is transmitted to the CCU 200 by the CSS 300,the CCU 200 selects a particular one of the copiers 100 by theidentification of the copier included in the request, and transmits therequest to the selected one of the copiers 100.

With respect to each of the remote message key transmission block, theS/D error remote message block and the advance warning remote messageblock, a destination telephone number, the number of redials, a redialperiod, and conditions of data transmission to the CSS 300 in the remotemessage transmission are retained in the CCU 200 as shown in FIG. 11. Inaddition, in the advance warning remote message block, a notificationtime (at which a remote message is transmitted to the CSS 300) isfurther retained in the CCU 200.

Further, in the total counter value transmission process block in theparameters of the CCU 200, a total counter value collection time, adestination telephone number, and transmission date and time areretained as shown in FIG. 11. In the telephone setting block, a dialmode setting (a dial pulse or a dial tone), and a dial pulse periodsetting are retained. Further, with respect to each of the respectiveblocks in the parameters of the CCU 200, a check sum is provided for anerror detection. The parameters of the CCU 200 can be set or rewrittenby the CSS 300 through a data transmission from the CSS 300 to the CCU200 via the PSN 250. Alternatively, a portable special device forparameter setting may be connected to the CCU 200 so as to set orrewrite the parameters of the CCU 200 by using the special device. Inthe image forming device management system of the present invention, atotal counter of the copier 100 is usually non-resettable, and the totalcounter value output by the total counter is an accumulated valueincremented from an initial value, and indicates a total of copy sheetsfor which image formation is performed by the copier 100.

1.6 Data Format of Messages

FIG. 12A, FIG. 12B and FIG. 12C show data formats of messages when aremote message transmission is performed.

FIG. 12A shows a data format of a remote message sent from the copier100 to the CCU 200. As shown in FIG. 12A, the remote message includes amessage code in the first field, and the number of jams, the number ofself-diagnostic (S/D) errors, the number of copy sheets and a state ofthe copier in the subsequent fields. The message code in the first fieldindicates which of a remote message key transmission, an S/D errorremote message transmission and an advance warning remote messagetransmission is related to that remote message. The state of the copierin the final field indicates various states of the copier, including alack of a replenishment-part, such as toner, oil or paper, an output ofa certain sensor, a setting of an adjustment point, and a state ofconnection of the copier elements.

FIG. 12B shows a data format of a remote message sent from the CCU 200to the CSS 300. As shown in FIG. 12B, the remote message includes amodel number and serial number in the first field, and the message code,the number of S/D errors, the state of the copier and an occurrence timein the subsequent fields. The model number and the serial number in thefirst field are specific to the originating copier 100. The messagecode, the number of jams, the number of S/D errors, the number of copysheets, and the state of the copier in the subsequent fields are thesame as those of the message sent from the copier 100. The occurrencetime in the final field indicates a time the remote message is produced,and this time is output by the clock 209 of the CCU 200. The contents ofthe subsequent fields (except the final field) of the remote messagesent from the CCU 200 to the CSS 300 may vary according to theparameters of the CCU 200. In the example of FIG. 12B, the parameters ofthe CCU 200 are set such that the remote message includes only themessage code, the number of the S/D errors and the state of the copier.

FIG. 12C shows a data format of a response sent from the CCU 200 to thecopier 100. As shown in FIG. 12C, the response includes a response codein the first field and the contents of the response in the final field.

FIG. 13A, FIG. 13B and FIG. 13C show respective data formats of messageswhen an access request is transmitted to the copier 100 (or thedestination copier 100) by the CSS 300.

FIG. 13A shows respective data formats of each of a read request sentfrom the CSS 300 to the CCU 200, a read request sent from the CCU 200 tothe copier 100, a response sent from the copier 100 to the CCU 200, anda response sent from the CCU 200 to the CSS 300. As shown in FIG. 13A,the read request, sent to the CCU 200 by the CSS 300, includes a modelnumber and serial number in the first field, and a read request code andan item code in the subsequent fields. The model number and the serialnumber in the first field of this message indicates an identification ofthe copier 100 which is to be accessed by the CSS 300 by the readrequest. The read request, sent to the copier 100 by the CCU 200,includes the read request code in the first field and the item code inthe second field, which are the same as corresponding ones of the readrequest sent to the CCU 200 by the CSS 300.

Further, as shown in FIG. 13A, the response, sent to the CCU 200 by thecopier 100, includes a read response code in the first field, and anitem code and a read data in the subsequent fields. The read data in thefinal field of this message indicates the result in response to theaccess request made by the CSS 300. The response, sent to the CSS 300 bythe CCU 200, includes the model number and the serial number in thefirst field, and the read response code, the item code and the read datain the subsequent fields. The model number and the serial number in thefirst field of this message indicate the identification of the copier100.

FIG. 13B shows respective data formats of each of a write request sentfrom the CSS 300 to the CCU 200, a write request sent from the CCU 200to the copier 100, a response sent from the copier 100 to the CCU 200and a response sent from the CCU 200 to the CSS 300. As shown in FIG.13B, the messages in the write request case are essentially the same ascorresponding messages in the read request case of FIG. 13A except forthe following points. Both the write request sent to the CCU 200 by theCSS 300 and the write request sent to the copier 100 by the CCU 200additionally include a writing data in the respective final fields. Boththe response sent to the CCU 200 by the copier 100 and the response sentto the CSS 300 by the CCU 200 include the written data in the respectivefinal fields instead of the read data in the response of FIG. 13A.Usually, the written data of the response sent by the copier 100 is thesame as the writing data of the write request sent by the CSS 300.However, when the writing data received from the CSS 300 is out of aneffective data range of the copier 100, the written data of the responsesent by the copier 100 may be rounded within the effective data range.

FIG. 13C shows respective data formats of each of an execute requestsent from the CSS 300 to the CCU 200, an execute request sent from theCCU 200 to the copier 100, a response sent from the copier 100 to theCCU 200 and a response sent from the CCU 200 to the CSS 300. As shown inFIG. 13C, the messages in the execute request case are essentially thesame as corresponding messages in the read request case of FIG. 13Aexcept for the following points. Both the execute request sent to theCCU 200 by the CSS 300 and the execute request sent to the copier 100 bythe CCU 200 additionally include a subsidiary parameter in therespective final fields. The subsidiary parameter indicates asupplementary command parameter of the execute request other than theitem code. Both the response sent to the CCU 200 by the copier 100 andthe response sent to the CSS 300 by the CCU 200 include the executionresult in the respective final fields instead of the read data in theresponses of FIG. 13A.

FIG. 14A, FIG. 14B and FIG. 14C show data formats of messages when anaccess request is transmitted to the CCU 200 by the CSS 300.

As shown in FIG. 14A through FIG. 14C, the messages in the CSS-to-CCUaccess request case are essentially the same as corresponding messagesin the CSS-to-copier access request case of FIG. 13A through FIG. 13Cexcept for the following points. Both the access requests sent to theCCU 200 by the CSS 300 and the responses sent to the CSS 300 by the CCU200 include a CCU device code in the respective first fields as anidentification of the CCU 200 instead of the identification (or themodel number and the serial number) of the copier 100 in theCSS-to-copier access request case of FIG. 13A through FIG. 13C.

FIG. 15A and FIG. 15B show data formats of messages when a read requestis transmitted to the copier 100 by the CCU 200.

As shown in FIG. 15A, the read request sent to the copier 100 by the CCU200 in the CCU-to-copier case is the same as the corresponding messagein the CSS-to-copier read request case of FIG. 13A. As shown in FIG.15B, the response sent to the CCU 200 by the copier 100 in theCCU-to-copier case is the same as the corresponding message in theCSS-to-copier response case of FIG. 13A. Hence, the copier 100 dealswith the messages in the same manner for both the CCU-to-copier readaccess case and the CSS-to-copier read access case.

1.7 Remote Message Transmission Process

1.7.1 Remote Message Transmission Process by Copier

Next, a description will be given of a remote message transmissionprocess performed by the copier 100 in the first embodiment, withreference to FIG. 16 through FIG. 19.

FIG. 16 shows a remote message transmission process performed by the CPU1001 of the copier 100 of FIG. 1 in the first embodiment. As shown inFIG. 16, at the start of the remote message transmission process, theCPU 1001 of the copier 100 at step S1 determines whether the remotemessage (R/M) enable switch 1032 (FIG. 2) is in its ON state.

When the result at the step S1 is affirmative, the CPU 1001 at step S2determines whether the remote message key of the operation part 1010(FIG. 2) is in its ON state. Otherwise, the remote message transmissionprocess of FIG. 16 at the present cycle ends.

When the result at the step S2 is affirmative, the CPU 1001 at step S3performs a remote message (R/M) key transmission sub-process. Thecontrol of the CPU 1001 is transferred to a start of the R/M keytransmission sub-process shown in FIG. 17, which will be describedbelow.

When the result at the step S2 is negative, the CPU 1001 at step S4determines whether a self-diagnostic (S/D) error has occurred. When theresult at the step S4 is affirmative, the CPU 1001 at step S5 performs aself-diagnostic (S/D) error remote message sub-process. The control ofthe CPU 1001 is transferred to a start of the S/D error remote messagesub-process shown in FIG. 18, which will be described below.

When the result at the step S4 is negative, the CPU 1001 at step S6determines whether an advance warning has been issued. When the resultat the step S6 is affirmative, the CPU 1001 at step S7 performs anadvance warning (A/W) remote message sub-process. The control of the CPU1001 is transferred to a start of the A/W remote message sub-processshown in FIG. 19, which will be described below. Otherwise, the remotemessage transmission process of FIG. 16 at the present cycle ends.

FIG. 17 shows a remote message (R/M) key transmission sub-process in theremote message transmission process of FIG. 16.

As shown in FIG. 17, at the start of the R/M key transmissionsub-process, the CPU 1001 at step S11 transmits a remote message to theCCU 200 in response to the ON state of the remote message key. After thestep S11 is performed, the CPU 1001 at step S12 determines whether anend-of-transmission (EOT) signal from the CCU 200 is normally receivedby the copier 100.

When the result at the step S12 is affirmative, the CPU 1001 at step S13resets a time-out timer to zero. Otherwise the CPU 1001 at step S16displays a transmission error message on the operation part 1010 anddoes not perform the step S13.

After the step S13 is performed (or the time-out timer is reset tozero), the CPU 1001 at step S14 determines whether a response messagesent by the CCU 200 in reply to the R/M key remote message has beenreceived by the copier 100. The CPU 1001 at step S15 determines whetherthe time-out timer exceeds a given waiting period (for example, threeminutes).

When the result at the step S15 is affirmative (the time-out timerexceeds three minutes), the CPU 1001 performs the above step S16 (inwhich the transmission error message is displayed). Otherwise the CPUrepeats the above step S14.

When the result at the step S14 is affirmative (or the response messageof the CCU 200 is received), the CPU 1001 at step S17 determines whetherthe response message of the CCU 200 indicates an acknowledgement ofreceipt of the remote message sent to the CCU 200 by the copier 100.

When the result at the step S17 is negative, the CPU 1001 performs theabove step S16 (or the transmission error message is displayed on theoperation part 1010). On the other hand, when the result at the step S17is affirmative, the CPU 1001 at step S18 displays a transmission endmessage for the transmitted remote message on the operation part 1010.After the step S18 is performed, the R/M key transmission sub-processends.

FIG. 18 shows a self-diagnostic (S/D) error remote message sub-processin the remote message transmission process of FIG. 16.

As shown in FIG. 18, at the start of the S/D error remote messagesub-process, the CPU 1001 at step S21 transmits a remote message to theCCU 200 in response to the self-diagnostic error having occurred. Afterthe step S21 is performed, the CPU 1001 at step S22 determines whetheran end-of-transmission (EOT) signal from the CCU 200 is normallyreceived by the copier 100.

When the result at the step S22 is affirmative, the CPU 1001 at step S23resets a time-out timer to zero. Otherwise the CPU 1001 at step S26displays a transmission error message on the operation part 1010 anddoes not perform the step S23.

After the step S23 is performed (or the time-out timer is reset tozero), the CPU 1001 at step S24 determines whether a response messagesent by the CCU 200 in reply to the S/D error remote message has beenreceived by the copier 100. The CPU 100 at step S25 determines whetherthe time-out timer exceeds a given waiting period (for example, twentyminutes).

When the result at the step S25 is affirmative (the time-out timerexceeds twenty minutes), the CPU 1001 performs the above-mentioned stepS26 (in which the transmission error message is displayed). Otherwisethe CPU repeats the step S24.

When the result at the step S24 is affirmative (or the response of theCCU 200 is received), the CPU 1001 at step S27 determines whether theresponse message of the CCU 200 indicates an acknowledgement of receiptof the remote message sent by the copier 100.

When the result at the step S27 is negative, the CPU 1001 performs theabove step S26 (or the transmission error message is displayed on theoperation part 1010). On the other hand, when the result at the step S27is affirmative, the CPU 1001 at step S28 displays a transmission endmessage for the transmitted remote message on the operation part 1010.After the step S28 is performed, the A/W remote message sub-processends.

FIG. 19 shows an advance warning (A/W) remote message sub-process in theremote message transmission process of FIG. 16.

As shown in FIG. 19, at the start of the A/W remote message sub-process,the CPU 1001 at step S31 transmits a remote message to the CCU 200 inresponse to the advance warning. After the step S31 is performed, theA/W remote message sub-process of FIG. 19 ends.

1.7.2 Access Request from CCU to Copier

A description will be given of a remote message transmission processperformed by the copier 100 when an access request is transmitted to thecopier 100.

FIG. 20 shows a remote message transmission process performed by thecopier 100 when an access request is sent to the copier 100 by the CCU200.

As shown in FIG. 20, at the start of the remote message transmissionprocess, the CPU 1001 of the copier 100 at step S41 determines whetherthe remote message enable switch 1032 (FIG. 2) is in its ON state.

When the result at the step S41 is affirmative (or the switch 1032 is inthe ON state), the CPU 1001 at step S42 determines whether thecommunication interface unit 1004 contains an access request sent to thecopier 100 by the CCU 200. Otherwise the CPU 1001 ends the remotemessage transmission process of FIG. 20 and does not perform the stepS42.

When the result at the step S42 is affirmative, the CPU 1001 at step S43receives the access request contained in the communication interfaceunit 1004. After the step S43 is performed, the CPU 1001 at step S44determines whether the received access request is a read request sent tothe copier 100 by the CCU 200.

When the result at the step S44 is affirmative, the CPU 1001 at step S45performs a read sub-process. The control of the CPU 1001 is transferredto a start of the read sub-process shown in FIG. 21, which will bedescribed below.

When the result at the step S44 is negative, the CPU 1001 at step S46determines whether the received access request is a write request sentto the copier 100 by the CCU 200.

When the result at the step S46 is affirmative, the CPU 1001 at step S47performs a write sub-process. The control of the CPU 1001 is transferredto a start of the write sub-process shown in FIG. 22, which will bedescribed below.

When the result at the step S46 is negative, the CPU 1001 at step S48determines whether the received access request is an execute requestsent to the copier 100 by the CCU 200.

When the result at the step S48 is affirmative, the CPU 1001 at step S49performs an execute sub-process. The control of the CPU 1001 istransferred to a start of the execute sub-process shown in FIG. 23,which will be described below. Otherwise it is determined that thereceived access request does not match any request code, and the CPU1001 at step S50 transmits an error code from the copier 100 to the CCU200. After the step S50 is performed, the remote message transmissionprocess of FIG. 20 at the present cycle ends.

FIG. 21 shows a read sub-process in the remote message transmissionprocess of FIG. 20.

As shown in FIG. 21, at the start of the read sub-process, the CPU 1001at step S51 determines whether the item code of the received requestcorrectly matches a predetermined code. When the result at the step S51is affirmative, the CPU 1001 at step S52 transmits a response to thereceived request to the CCU 200. On the other hand, when the result atthe step S51 is negative, it is determined that the item code of thereceived request does not match the predetermined code, and the CPU 1001at step S53 transmits an error code to the CCU 200.

After the step S52 or the step S53 is performed, the read sub-process atthe present cycle ends.

FIG. 22 shows a write sub-process in the remote message transmissionprocess of FIG. 20.

As shown in FIG. 22, at the start of the write sub-process, the CPU 1001at step S61 determines whether the item code of the received writerequest correctly matches a predetermined code. When the result at thestep S61 is affirmative, the CPU 1001 at step S62 determines whether thewriting data of the received write request is in an effective data rangeof the copier 100.

When the result at the step S62 is affirmative, the CPU 1001 at step S63writes the writing data of the received write request to the copier 100.After the step S63 is performed, the CPU 1001 at step S64 transmits aresponse, including the written data, to the CCU 200. After the step S64is performed, the CPU 1001 ends the write sub-process of FIG. 22.

When the result at the step S62 is negative, the CPU 1001 at step S65determines whether the writing data of the received write request can berounded within the effective data range of the copier 100.

When the result at the step S65 is affirmative, the CPU 1001 at step S66writes the rounded writing data to the copier 100. After the step S66 isperformed, the CPU 1001 performs the above step S64. On the other hand,when the result at the step S65 is negative, the CPU 1001 at step S67transmits an error code to the CCU 200. After the step S67 is performed,the CUP 1001 ends the write sub-process of FIG. 22.

FIG. 23 shows an execute sub-process in the remote message transmissionprocess of FIG. 20.

As shown in FIG. 23, at the start of the execute sub-process, the CPU1001 at step S71 determines whether the item code of the receivedexecute request correctly matches a predetermined code. When the resultat the step S71 is negative, the CPU 1001 at step S76 transmits an errorcode to the CCU 200. On the other hand, when the result at the step S71is affirmative, the CPU 1001 at step S72 determines whether the receivedexecute request needs a subsidiary parameter.

When the result at the step S72 is negative, the CPU 1001 at step S73executes an operation on the copier 100 in accordance with the receivedexecute request. After the step S73 is performed, the CPU 1001 at stepS74 transmits a response, including the execution result, to the CCU 200from the copier 100. After the step S74 is performed, the CPU 1001 endsthe execute sub-process of FIG. 23.

When the result at the step S72 is affirmative, the CPU 1001 at step S75determines whether the subsidiary parameter of the received request isin an effective range of the copier 100.

When the result at the step S75 is affirmative, the CPU 1001 performsthe above steps S73 and S74. On the other hand, when the result at thestep S75 is negative, the CPU 1001 performs the above step S76 in whichan error code is transmitted to the CCU 200. After the step S76 isperformed, the CPU 1001 ends the execute sub-process of FIG. 23.

1.7.3 Communication Sequences of CCU and Copier

FIG. 24 shows a communication sequence of the CCU 200 and the copier 100during an idle condition. Suppose that the five copiers 100 areconnected to the CCU 200, and the copiers 100 and the CCU 200 are in theidle condition.

As shown in FIG. 24, a polling (ENQ) of the CCU 100 to a specific one ofthe copiers 100 is sequentially performed for all the copiers 100 byusing a polling address of the specific one of the copiers 100. If thereis no message which should be transmitted to the CCU 200, each of thecopiers 100 sends back a negative acknowledgement (EOT) to the CCU 200in response to the polling. If the EOT signal is received from all thecopiers 100, the CCU 200 repeats the polling process.

FIG. 25 shows a communication sequence of the CCU 200 and the copier 100during a remote message transmission. Suppose that there is a remotemessage which should be transmitted from the copier#2 100 to the CCU200, and the copier#2 100 has a polling address “2”.

As shown in FIG. 25, after the polling (P2ENQ) of the CCU 200 to thecopier#2 is performed by using the polling address “2”, the copier#2transmits the message through the RS-485 interface 205 to the CCU 200.After the transmission of the message, the CCU 200 transmits anacknowledgment (ACK) to the copier#2 at the polling address “2”. Afterthe ACK signal is received, the copier#2 transmits the EOT signal to theCCU 200.

FIG. 26 shows a communication sequence of the CCU 200 and the copier 100during a remote message receiving. Suppose that there is a transmissionresult message which should be transmitted from the CCU 200 to thecopier#5 100, and the copier#5 100 has a selecting address “5”.

As shown in FIG. 26, after the polling process for all the copiers 100is terminated by the CCU 200, a selecting (P5ENQ) of the CCU 200 to thecopier#5 100 is performed by using the selecting address “5”. After theselecting is performed, the copier#5 100 at the selecting address “5”transmits an acknowledgement (ACK) to the CCU 200. The CCU 200 transmitsthe transmission result message through the RS-485 interface 205 to thecopier#5 100 at the selecting address “5”. After the transmission of themessage, the copier#5 100 at the selecting address “5” transmits anacknowledgment (ACK) to the CCU 200. After the ACK signal is received,the CCU 200 transmits the EOT signal to the copier#5 100 at theselecting address “5”. Then, the control of the CCU 200 is transferredto the polling process.

FIG. 27 shows a communication sequence of the CCU 200 and the copier 100when an access request is transmitted to the copier 100 by the CCU 200(or by the CSS 300). Suppose that the access request is transmitted tothe copier#3 100 by the CCU 200 or the CSS 300, and the copier#3 100 hasa selecting address “3”.

As shown in FIG. 27, after the selecting (P3ENQ) of the CCU 200 to thecopier#3 100 is performed by using the selecting address “3”, thecopier#3 100 at the selecting address “3” transmits an acknowledgement(ACK) to the CCU 200. The CCU 200 transmits the access request (which isone of a read request, a write request and an execute request) throughthe RS-485 interface 205 to the copier#3 100 at the selecting address“3”. After the transmission of the access request, the copier#3 100 atthe selecting address “3” transmits an acknowledgment (ACK) to the CCU200. After the ACK signal is received, the CCU 200 transmits the EOTsignal to the copier#3 100 at the selecting address “3”. Then, thecontrol of the CCU 200 is transferred to the polling process for thecopier#3 100 at the address “3”.

1.8 Signal Line Separation Message Process

1.8.1 No-Communication Counter Method

FIG. 28 shows a signal line separation message process performed by thecopier 100 in a first embodiment of the image forming device managementsystem of the present invention. The signal line separation messageprocess of FIG. 28 utilizes a no-communication (N/C) counter in the CPU1001 of the copier 100.

In the present embodiment, the polling of the CSS 300 for the copiers100 is periodically performed. The period of performing the pollingprocess is, for example, once for 24 hours or less. Further, in thepresent embodiment, the signal line separation message process of FIG.28 is periodically initiated by the CPU 1001 by using a timer.

As shown in FIG. 28, the CPU 1001 at step S101 determines whether amessage display flag is set to “1” (or ON state). When the result at thestep S101 is affirmative, the CPU 101 at step S103 determines whetherthe N/C counter is larger than a given value.

On the other hand, when the result at the step S101 is negative, the CPU101 at step S102 increments the N/C counter. After the step S102 isperformed, the CPU 101 performs the above step S103.

When the result at the step S103 is affirmative (or the N/C counter>thegiven value), the CPU 1001 at step S104 displays a signal lineseparation message on the operation part 1010. The signal lineseparation message indicates to the user of the copier 100 that aseparation of the signal line between the CCU 200 and the copier 100occurs. After the step S104 is performed, the CPU 1001 at step S105 setsthe message display flag to “1”. After the step S105 is performed, thesignal line separation message process of FIG. 28 ends.

On the other hand, when the result at the step S103 is negative (or theN/C counter<the given value), the CPU 1001 at step S106 determineswhether the message display flag is set to “1”. When the result at thestep S106 is affirmative, the CPU 101 at step S107 eliminates the signalline separation message from the operation part 1010. After the stepS107 is performed, the CPU 1001 at step S108 resets the message displayflag to “0” (or OFF state). After the step S108 is performed, the signalline separation message process of FIG. 28 ends.

On the other hand, when the result at the step S106 is negative, the CPU101 ends the signal line separation message process of FIG. 28 and doesnot performs the above steps S107 and S108.

FIG. 29 shows a no-communication counter resetting process performed bythe copier 100 in the first embodiment. In the present embodiment, theno-communication counter resetting process of FIG. 29 is periodicallyinitiated by the CPU 1001 by using a timer.

As shown in FIG. 29, the CPU 1001 at step S201 determines whether datasent from the CSS 300 or the CCU 200 is received by the communicationinterface unit 1004. When the result at the step S201 is affirmative,the CPU 1001 at step S202 resets the N/C counter to “0”. After the stepS202 is performed, the no-communication counter resetting process ofFIG. 29 ends. When the result at the step S201 is negative, the CPU 1001ends the no-communication counter resetting process of FIG. 28, and doesnot perform the above step S202.

1.8.2 CCU Selecting Method

In the signal line separation message process of FIG. 28, the period oftime during which the copier 100 has no signal from the CCU 200 or theCSS 300 is detected by using the no-communication (N/C) counter.Alternatively, the signal line separation message process may beperformed by using a different method.

FIG. 30 shows a communication sequence of the CCU 200 and the copier 100when a signal line separation message process is performed by using aselecting of the CCU 200 to the copiers 100.

In the present embodiment, the selecting of the CCU 200 to the copier100 (or one of the copiers 100) is periodically performed. The period ofperforming the selecting process is, for example, once for 24 hours orless. In the present embodiment, the signal line separation process isperformed by using the selecting of the CCU 200 to the copier 100.

As shown in FIG. 30, the selecting (ENQ) is periodically transmittedfrom the CCU 200 to the copier 100 once for 24 hours or less. If thereis a data link between the CCU 200 and the copier 100 is established atthat time, the copier 100 transmits an acknowledgement (ACK) to the CCU200 in response to the selecting (ENQ). After the ACK signal is receivedby the CCU 200, the CCU 200 transmits a message to the copier 100. Afterthe message is received by the copier 100, the copier 100 transmits anacknowledgment (ACK) to the CCU 200. Further, after the ACK signal isreceived by the CCU 200, the CCU 200 transmits an EOT signal to thecopier 100. When the EOT signal is received by the copier 100, theselecting process is normally terminated.

Accordingly, in the present embodiment, when all the conditions for theabove-mentioned selecting process are met, it is determined that thecopier 100 normally communicates with the CCU 200. In this case, the CPU1001 performs only the steps S106-S108 of the signal line separationmessage process of FIG. 28. When any of the conditions for theabove-mentioned selecting process is not met, it is determined that thecopier 100 has no signal from the CCU 200. In this case, the CPU 1001performs only the steps S104 and S105 of the signal line separationmessage process of FIG. 28.

1.8.3 CSS Selecting Method

FIG. 31 shows a communication sequence of the CSS 300 and the copier 100when a signal line separation message process is performed by using aselecting of the CSS 300 to the copier 100.

In the present embodiment, the selecting of the CSS 300 to the copier100 is performed when an access request is transmitted to the copier100. In the present embodiment, the signal line separation process isperformed by using the selecting of the CSS 300 to the copier 100.

As shown in FIG. 31, the selecting of the CSS 300 is transmitted throughthe CCU 200 to the copier 100 before transmitting an access request tothe copier 100. If there is a data link between the CCU 200 and thecopier 100 is established at that time, the copier 100 transmits anacknowledgement (ACK) to the CCU 200 in response to the selecting. Afterthe ACK signal is received by the CCU 200, the CCU 200 transmits theaccess request (or the message) to the copier 100. After the message isreceived by the copier 100, the copier 100 transmits an acknowledgment(ACK) to the CCU 200. Then, the selecting of the CSS 300 to the copier100 is normally terminated.

Accordingly, in the present embodiment, when all the conditions for theabove-mentioned selecting process are met, it is determined that thecopier 100 normally communicates with the CCU 200. In this case, the CPU1001 performs only the steps S106-S108 of the signal line separationmessage process of FIG. 28. When any of the conditions for theabove-mentioned selecting process is not met, it is determined that thecopier 100 has no signal from the CCU 200. In this case, the CPU 1001performs only the steps S104 and S105 of the signal line separationmessage process of FIG. 28.

1.8.4 CCU Polling Method

FIG. 32 shows a communication sequence of the CCU 200 and the copier 100when a signal line separation message process is performed by using apolling of the CCU 200 to the copiers 100.

In the present embodiment, the polling of the CCU 200 to the copiers 100is periodically performed. The period of performing the polling processis, for example, once for one minute. In the present embodiment, thesignal line separation process is performed by using the polling of theCCU 200 to the copiers 100.

As shown in FIG. 32, the polling (ENQ) is transmitted from the CCU 200to one of the copiers 100. If there is a data link between the CCU 200and the copier 100 is established at that time, the ENQ signal from theCCU 200 is received by the copier 100. In response to the polling (ENQ),the copier 100 transmits an acknowledgement (ACK) or anend-of-transmission (EOT) to the CCU 200. When the ACK or EOT signal isreceived by the CCU 200, the polling process is normally terminated.

Accordingly, in the present embodiment, when the condition for theabove-mentioned polling process is met, it is determined that the copier100 normally communicates with the CCU 200. In this case, the CPU 1001performs only the steps S106-S108 of the signal line separation messageprocess of FIG. 28. When the condition for the above-mentioned pollingprocess is not met, it is determined that the copier 100 has no signalfrom the CCU 200. In this case, the CPU 1001 performs only the stepsS104 and S105 of the signal line separation message process of FIG. 28.

1.8.5 Detection of Voltage of Terminal of Communication Interface Unit

FIG. 33 is a diagram for explaining a signal line separation messageprocess which is performed by using a detection of a voltage of areceiving terminal 100R of the communication interface unit 1004 of thecopier 100.

In the image forming device management system of the present embodiment,the data communication between the CCU 200 and the copier 100 is carriedout through a communication line, and the communication line isconnected to the communication interface unit 1004 of the copier 100 asshown in FIG. 2. A transmitting signal on the communication line isinput to or output from the communication interface unit 1004 of thecopier 100. Hence, by detecting a voltage of a receiving terminal of thecommunication interface unit 1004, it is possible to determine whetherthe copier 100 has a signal from the CCU 200. For example, when thevoltage of the receiving terminal does not change over 10 minutes, it isdetermined that a separation of the signal line between the CCU 200 andthe copier 100 occurs.

As shown in FIG. 33, a receiving signal line 1004R and a transmittingsignal line 1004T are connected at one end to the receiving terminal anda transmitting terminal of the communication interface unit 1004 of thecopier 100. The signal lines 1004R and 1004T are connected at the otherends to the CCU 200.

FIG. 34 shows a signal line separation message process performed by theCPU 1001 of the copier 100 by using a detected voltage of the receivingterminal of the communication interface unit 1004 of the copier 100. Inthe present embodiment, the signal line separation message process ofFIG. 34 is periodically initiated by the CPU 1001 every one second.

As shown in FIG. 34, at the start of the signal line separation messageprocess, the CPU 1001 at step S121 waits for one second. After the stepS121 is performed, the CPU 1001 at step S122 determines whether adetected voltage of the receiving terminal (1004R) of the communicationinterface unit 1004 is in a high state.

When the result at the step S122 is negative (or the detected voltage isin a low state), the CPU 1001 at step S123 determines whether a previousdetected voltage of the receiving terminal 1004R is in a high state.When the result at the step S123 is negative (or the detected voltage isin a low state), the CPU 1001 at step S124 increments a counter.

On the other hand, when the result at the step S123 is affirmative (orthe detected voltage is in the high state), the detected voltage of thereceiving terminal 1004R changes from the low state to the high state.In this case, the CPU 1001 at step S125 resets the counter to “0”. Afterthe step S125 is performed, the CPU 1001 performs the step S124 in whichthe counter is incremented.

When the result at the step S122 is affirmative (or the detected voltageis in the high state), the CPU 1001 at step S126 determines whether theprevious detected voltage of the receiving terminal 1004R is in the lowstate. When the result at the step S126 is negative, the detectedvoltage of the receiving terminal 1004R does not change. In this case,the CPU 1001 performs the above step S124 in which the counter isincremented. On the other hand, when the result at the step S126 isaffirmative, the detected voltage of the receiving terminal 1004 changesfrom the low state to the high state. In this case, the CPU 1001performs the above steps S125 and S124.

After the step S124 is performed, the CPU 1001 at step S127 determineswhether the counter is above a given value. When the result at the stepS127 is affirmative, the CPU 1001 at step S128 displays a signal lineseparation message on the operation part 1010 similar to the step S104of FIG. 28. When the result at the step S127 is negative, the CPU 1001at step S129 eliminates the signal line separation message from theoperation part 1010 similar to the step S107 of FIG. 28. In the presentembodiment, the given value with which the counter is compared is presetto be equivalent to 10 minutes or longer.

1.8.6 Connection Detecting Line between CCU and Copier

FIG. 35A and FIG. 35B show a signal line separation message processwhich is performed by using a connection detecting line provided betweenthe CCU 200 and the copier 100.

As shown in FIG. 35A, the receiving signal line 1004R and thetransmitting signal line 1004T are connected at one end to the receivingterminal and the transmitting terminal of the communication interfaceunit 1004 of the copier 100. The signal lines 1004R and 1004T areconnected at the other ends to the CCU 200. Further, a connectiondetecting line is provided between the CCU 200 and the communicationinterface unit 1004. As shown in FIG. 35B, the connection detecting lineis grounded on the side of the CCU 200, and the connection detectingline is connected at the other end to a terminal of the communicationinterface unit 1004. A reference voltage (5 V) is supplied through aresistor (R) to the connection detecting line for detecting a voltage ofthe terminal of the communication interface unit 1004. The CPU 1001detects a voltage of the connection detecting line.

FIG. 36 shows a signal line separation message process performed by theCPU 1001 of the copier 100 using the connect detection line between theCCU 200 and the copier 100. In the present embodiment, the signal lineseparation message process of FIG. 36 is periodically initiated by theCPU 1001 every one second.

As shown in FIG. 36, at the start of the signal line separation messageprocess, the CPU 1001 at step S131 waits for one second. After the stepS131 is performed, the CPU 1001 at step S132 determines whether adetected voltage of the connection detecting line is in a high state.

When the result at the step S132 is negative (or the detected voltage isin a low state), it is determined that there is no separation of thesignal line between the CCU 200 and the copier 100. In this case, theCPU 1001 at step S133 resets the counter to “0”. After the step S133 isperformed, the CPU 1001 at step S134 eliminates the signal lineseparation message from the operation part 1010 similar to the step S107of FIG. 28.

On the other hand, when the result at the step S132 is affirmative (orthe detected voltage is in the high state), the CPU 1001 at step S135increments the counter. After the step S135 is performed, the CPU 1001at step S136 determines whether the counter is larger than a givenvalue.

When the result at the step S136 is affirmative (or the counter>thegiven value), the CPU 1001 at step S137 displays the signal lineseparation message on the operation part 1010 similar to the step S104of FIG. 28. When the result at the step S136 is negative (or thecounter<the given value), the CPU 1001 performs the above step S134 inwhich the signal line separation message is eliminated from theoperation part 1010 similar to the step S107 of FIG. 28. In the presentembodiment, the given value with which the counter is compared is presetto be equivalent to 10 minutes or longer.

2. Second Embodiment

The present embodiment of the image forming device management system ischaracterized in that the image forming device 100 of concerneffectively inhibits an automatic message transmission through the CCU200 to the CSS 300 when a jam of the image forming device 100continuously occurs.

In the present embodiment, the structure of the image forming devicemanagement system, the structure of the image forming device 100, thestructure of the CCU 200, the structure of the CSS 300, thecommunication sequences, the data format of the messages, and the remotemessage transmission process are essentially the same as correspondingelements of the previous embodiment described in the above sections 1.1through 1.7.

A description will now be given of only features of the secondembodiment of the image forming device management system which aredifferent from those of the previous embodiment.

2.1 Jam Detection Process

2.1.1 First Jam Detection Process

FIG. 37 shows a first jam detection process performed by the CPU 1001the copier 100 in the present embodiment of the image forming devicemanagement system. The first jam detection process of FIG. 37 isinitiated by the CPU 1001 every time an internal mechanical condition ofthe copier 100 changes.

As shown in FIG. 37, at the start of the first jam detection process,the CPU 1001 at step S201 determines whether a jam of the copier 100 hasoccurred. When the jam has occurred, the CPU 1001 at step S202increments a continuous jam counter.

When no jam occurs, the CPU 1001 at step S207 resets the continuous jamcounter to “0”. After the step S207 is performed, the CPU 1001 ends thefirst jam detection process of FIG. 37.

After the step S202 is performed, the CPU 1001 at step S203 determineswhether the continuous jam counter is equal to a given value. When theresult at the step S203 is affirmative, the CPU 1001 at step S204performs an alarm message process in which an alarm message isautomatically transmitted through the CCU 200 to the CSS 300. After thestep S204 is performed, the CPU 1001 ends the first jam detectionprocess of FIG. 37.

On the other hand, when the result at the step S203 is negative, the CPU1001 at step S205 determines whether the continuous jam counter is abovethe given value. When the result at the step S205 is affirmative (or thecontinuous jam counter>the given value), the CPU 1001 at step S206 setsthe continuous jam counter so as to be equal to the given value. Afterthe step S206 is performed, the CPU 1001 ends the first jam detectionprocess of FIG. 37. In this case, the CPU 1001 does not perform thealarm message process of the step S204. Therefore, it is possible toeffectively inhibit the automatic message transmission of the copier 100to the CSS 300 when a jam of the copier 100 continuously occurs.

When the result at the step S205 is negative (or the continuous jamcounter<the given value), the CPU 1001 ends the first jam detectionprocess of FIG. 37.

2.1.2 Second Jam Detection Process

FIG. 38 shows a second jam detection process performed by the CPU 1001of the copier 100 in the present embodiment. The second jam detectionprocess of FIG. 38 is initiated by the CPU 1001 every time an internalmechanical condition of the copier 100 changes.

FIG. 39 shows the second jam detection process performed by the CPU 1001of the copier 100 in the present embodiment. The second jam detectionprocess of FIG. 39 is periodically initiated by the CPU 1001 by using atimer.

In the second jam detection process of FIG. 38, the CPU 1001 at stepS211 determines whether the copier 100 is in a jam state. When thecopier 100 is in the jam state, the CPU 1001 at step S212 determineswhether a long-period jam counter flag is equal to “0”.

When the copier 100 is not in a jam state, the CPU 1001 at step S214resets the long-period jam counter flag to “0”. After the step S214 isperformed, the CPU 1001 ends the second jam detection process of FIG.38.

When the result at the step S212 is negative (or the long-period jamcounter flag is not equal to “0”), the CPU 1001 ends the second jamdetection process of FIG. 38. On the other hand, when the result at thestep S212 is affirmative (or the long-period jam counter flag is equalto “0”), the CPU 1001 at step S213 sets the long-period jam counter flagto “1”. After the step S213 is performed, the CPU 1001 ends the secondjam detection process of FIG. 38.

In the second jam detection process of FIG. 39, the CPU 1001 at stepS221 determines whether the long-period jam counter flag is equal to“1”. When the result at the step S221 is affirmative, it is determinedthat the long-period jam counter should be set in an ON state to startcounting for the detection of a period for which the copier 100continues to be in the jam state. The CPU 1001 at step S222 incrementsthe long-period jam counter.

On the other hand, when the result at the step S221 is negative, it isdetermined that the long-period jam counter should be set in an OFFstate to stop counting. The CPU 1001 at step S226 resets the long-periodjam counter to “0”. After the step S226 is performed, the CPU 1001 endsthe second jam detection process of FIG. 39.

After the step S222 is performed, the CPU 1001 at step S223 determineswhether the long-period jam counter is above a given value. When theresult at the step S223 is negative, the CPU 1001 ends the second jamdetection process of FIG. 39. On the other hand, when the result at thestep S223 is affirmative, the CPU 1001 at step S224 performs along-period jam alarm message process in which a long-period jam alarmmessage is automatically transmitted through the CCU 200 to the CSS 300.After the step S224 is performed, the CPU 1001 at step S225 sets thelong-period jam counter flag to “2” and resets the long-period jamcounter to “0”. After the step S225 is performed, the CPU 1001 ends thefirst jam detection process of FIG. 39. Therefore, it is possible toeffectively inhibit the automatic message transmission of the copier 100to the CSS 300 when the copier 100 continues to be in the jam state fora long period.

2.2 CSS Function Setting Process

FIG. 40 shows a CSS function setting process performed by the CPU 1001of the copier 100 in the present embodiment. The CSS function settingprocess of FIG. 40 is periodically initiated by the CPU 1001 by using atimer.

As shown in FIG. 40, at the start of the CSS function setting process,the CPU 1001 at step S231 determines whether a CSS function flag isequal to “1”. When the result at the step S231 is affirmative, the CPUat step S232 determines whether a previous CSS function flag is equal to“0”. When the previous CSS function flag is equal to “0”, the CPU 1001at step S233 resets the continuous jam counter to “0”, resets thelong-period jam counter to “0”, and resets the long-period jam counterflag to “0”. After the step S233 is performed, the CPU 1001 performsstep S234.

On the other hand, when the previous CSS function flag is equal to “1”,the CPU 1001 at step S234 retains the previous CSS function flag in thememory of the copier 100. After the step S234 is performed, the CPU 1001terminates the CSS function setting process.

When the result at the step S231 is negative (or the CSS function flagis equal to “0”), the CPU 1001 at step S235 performs a remote message(R/M) inhibition process. After the R/M inhibition process is performed,the CPU 1001 of the copier 100 is inhibited from performing the R/Mtransmission to the CSS 300 or the statistical process. After the stepS235 is performed, the CPU 1001 performs the step S234.

3. Third Embodiment

The present embodiment of the image forming device management system ischaracterized in that the image forming device of concern starts anautomatic message transmission only in an appropriate situation when amaintenance service of the image forming device is performed by aserviceman.

In the present embodiment, the structure of the image forming devicemanagement system, the structure of the image forming device 100, thestructure of the CCU 200, the structure of the CSS 300, thecommunication sequences, the data format of the messages, and the remotemessage transmission process are essentially the same as correspondingelements of the previous embodiment described in the above sections 1.1through 1.7.

A description will now be given of only features of the third embodimentof the image forming device management system which are different fromthose of the previous embodiment.

3.1 Serviceman Maintenance Service Start/End Message Process (FirstExample)

FIG. 41 shows a maintenance service start/end message process which isperformed by the copier 100 in a third embodiment of the image formingdevice management system. The maintenance service start/end messageprocess of FIG. 41 is initiated when an event (which is either aserviceman visit message request or a serviceman visit end messagerequest) occurs.

As shown in FIG. 41, at the start of the maintenance service start/endmessage process, the CPU 1001 at step S301 determines whether aserviceman visit message is requested by the serviceman. When the resultat the step S301 is affirmative, the CPU 1001 at step S302 sets aserviceman visit flag to “1” (or an ON state). After the step S302 isperformed, the CPU 1001 terminates the maintenance service start/endmessage process.

When the result at the step S301 is negative (or the serviceman visitmessage is not requested), the CPU 1001 at step S303 determines whethera serviceman visit end message is requested by the serviceman. When theresult at the step S303 is affirmative, the CPU 1001 at step S304 resetsthe serviceman visit flag to “0” (or an OFF state). After the step S304is performed, the CPU 1001 terminates the maintenance service start/endmessage process of FIG. 41. In the present embodiment, the servicemanvisit flag is retained in the RAM 1003 which is a non-volatile (N/V)memory or a battery backup RAM. Hence, even when a power switch of thecopier 100 is turned OFF, it is possible to prevent the content of theserviceman visit flag from being lost.

FIG. 42 shows another maintenance service start/end message processperformed by the copier 100 in the third embodiment. The maintenanceservice start/end message process of FIG. 42 is initiated when an event(which is a remote message (R/M) process execute request) occurs.

As shown in FIG. 42, at the start of the maintenance service start/endmessage process, the CPU 1001 at step S311 determines whether a receivedremote message (R/M) process execute request is related to a R/M processdifferent than a replenishment part message process. When the result atthe step S311 is negative, the CPU 1001 ends the maintenance servicestart/end message process of FIG. 42. When the result at the step S311is affirmative, the CPU 1001 at step S312 determines whether theserviceman visit flag is equal to “1”.

When the result at the step S312 is affirmative (or the serviceman visitflag=1), the CPU 1001 at step S313 cancels the R/M process executerequest. After the step S313 is performed, the CPU 1001 terminates themaintenance service start/end message process of FIG. 42.

When the result at the step S312 is negative (or the serviceman visitflag=0), the CPU 1001 at step S314 performs the remote message (R/M)transmission process in response to the execute request. After the stepS314 is performed, the CPU 1001 terminates the maintenance servicestart/end message process of FIG. 42.

3.2 Serviceman Maintenance Service Start/End Message Process (SecondExample)

FIG. 43 shows a further maintenance service start/end message processwhich is performed by the copier 100 in the third embodiment. Themaintenance service start/end message process of FIG. 43 is initiatedwhen an event (which is either a serviceman visit message request or aserviceman visit end message request) occurs.

As shown in FIG. 43, at the start of the maintenance service start/endmessage process, the CPU 1001 at step S321 determines whether theserviceman visit message is requested by the serviceman. When the resultat the step S321 is affirmative, the CPU 1001 at step S322 sets theserviceman visit flag to “1”. After the step S322 is performed, the CPU1001 terminates the maintenance service start/end message process ofFIG. 43.

When the result at the step S321 is negative (or the serviceman visitmessage is not requested), the CPU 1001 at step S323 determines whetherthe serviceman visit end message is requested by the serviceman. Whenthe result at the step S323 is affirmative, the CPU 1001 at step S324resets the serviceman visit flag to “0”. After the step S324 isperformed, the CPU 1001 at step S325 resets the continuous jam counterto “0”, resets the long-period jam counter to “0”, and resets adoor-open time counter to “0”. After the step S325 is performed, the CPU1001 terminates the maintenance service start/end message process ofFIG. 43.

In the present embodiment, the continuous jam counter is used toautomatically transmit a continuous jam message to the CSS 300 when anumber of jams has continuously occurred on the copier 100. Thelong-period jam counter is used to automatically transmit a long-periodjam message to the CSS 300 when the copier 100 is continuously in a jamstate for a long period. The door-open time counter is used toautomatically transmit a long-period door-open message to the CSS 300when a door of the copier 100 is continuously open for a long period.

4. Fourth Embodiment

4.1 Structure of System

FIG. 44 shows a fourth embodiment of the image forming device managementsystem of the present invention. As shown in FIG. 44, in the imageforming device management system of the present embodiment, a pluralityof image forming devices 400 (such as copiers 401 through 405) areprovided. Although the image forming devices 400 may be copiers,facsimiles or printers, in the following description, for the sake ofconvenience, one of the image forming devices 400 will be called theimage forming device 400 or the copier 400 unless otherwise specified.

In the image forming device management system of FIG. 44, a datacommunication device DCD 420 is also provided, and each of the imageforming devices 400 is connected to the DCD 420. The DCD 420 is linkedto a central service station CSS 460 at a remote location via a publicswitched network PSN 450. The maintenance of the image forming devices400 are remotely controlled by the CSS 460 through the DCD 420 and thePSN 450 in a centralized manner. The CSS 460 in the present embodimentis essentially the same as the CSS 300 in the previous embodiments.

The DCD 420 in the present embodiment functions to selectively transmita control signal from the CSS 460 to one of the image forming devices400, and to transmit a message from one of the image forming devices 400to the CSS 460 through the PSN 450. A power switch of the DCD 420 iscontinuously turned ON for 24 hours, and the DCD 420 is capable ofalways communicating with the CSS 460 even when the image formingdevices 400 are in OFF state.

The interface between each copier 400 and the DCD 420 is provided by amultidrop connection which is in conformity with RS-485 standard. Thecommunication sequence between each copier 400 and the DCD 420 isperformed in accordance with basic data transmission procedures. The DCD420 can communicate with one of the copiers 400 after a data linkbetween the DCD 420 and the copier 400 is established by using acentralized polling/selecting control method. A specific device addresscan be set for each of the copiers 400 by setting an address settingswitch of each copier 400, and a polling address and a selecting addresscan be set for each copier 400 in accordance with the specific deviceaddress.

4.2 Data Communication Device (DCD)

FIG. 45 shows a data communication device DCD in the fourth embodimentof the image forming device management system.

As shown in FIG. 45, the DCD 420 generally has a control part 421, anauto dialer 422, and a switching control part 423. A telephone 424 isconnected to the switching control part 423. The control part 421controls the plurality of the image forming devices 400 and controlsreceiving of a signal sent through the PSN 450 to the DCD 420 by the CSS460. The auto dialer 422 functions to automatically send a call to theCSS 460 in accordance with a message sent by one of the image formingdevice 400. The switching control part 423 carries out a connectioncontrol to the PSN 450 and a switching of the DCD 420 to one of thetelephone 424 and the image forming device 400.

In the DCD 420 of FIG. 45, the control part 421 (the structure of whichis not shown in FIG. 45) includes a CPU which executes a controlprogram, a ROM which stores the control program and control datatherein, a RAM which provides a working storage area for the CPU whenexecuting the control program, a non-volatile (N/V) RAM which retainsoperating parameters by using a battery, a plurality of serialcommunication control units (CCU), an input/output (I/O) port, and areal-time (R/T) clock which provides a current time. The control part421 has the structure that is essentially the same as the structure of acontrol part of the image forming device 400 shown in FIG. 48. In thenon-volatile RAM of the control part 421, transmission data exchangedbetween the image forming devices 400 and the CSS 460, device codes andID codes of the image forming devices 400, a telephone number of the CSS460, the number of redials, a redial period and so on are stored.

4.3 Functions of System

The image forming device management system of FIG. 44 provides thefollowing functions:

(1) control of communications from the CSS 460 to the image formingdevices 400;

(2) control of communications from each image forming device 400 to theCSS 460 or communications from each image forming device 400 to the DCD420; and

(3) control by the DCD 420.

A description will now be given of these functions of the image formingdevice management system in the present embodiment.

4.3.1 Control of Communications from CSS to Copiers

The image forming device management system of FIG. 44 can read out orreset a total copy count, a copy count of each paper tray, a copy countof each sheet size, a total misfeed count, a misfeed count of each sheetsize and a misfeed count of each sheet transport position in aparticular one of the image forming devices 400.

The image forming device management system of FIG. 44 can set or readout adjustment values of a controlled voltage, current, resistance andtiming of each of various elements of each image forming device 400.

The image forming device management system of FIG. 44 can controltransmission and receiving of a response to one of the above-mentionedcontrols which is delivered to the CSS 460 by one of the image formingdevices 400.

The DCD 420 receives a command from the CSS 460 and performs a selectingto a particular one of the image forming devices 400 in accordance withthe command. When the selecting to the particular one of the imageforming devices 400 is performed by the DCD 420, one of the abovecontrols is carried out in the image forming device management system ofthe present embodiment.

FIG. 46 shows a selecting process performed to a particular one of theimage forming devices 400 by the DCD 420 in the fourth embodiment.Suppose that a particular one of the image forming devices 400 has adevice code, and a specific control code is assigned to indicate apredetermined selecting function.

At the start of the selecting process, the DCD 420 sends the specificcontrol code and the device code through the serial CCU to theparticular one of the image forming devices 400 (which will be calledthe copier 400). The copier 400 receives the specific control code andthe device code. After the specific control code is detected, the copier400 determines whether the received device code matches a device code ofthe copier 400. When the received device code matches the device code ofthe copier 400, the copier 400 recognizes that the selecting of the DCD420 is performed to the copier 400. Instead of the specific controlcode, a combination of certain codes may be used to indicate theselecting function.

When the copier 400 has a transmission data upon the selecting of theDCD 420 to the copier 400, the copier 400 outputs a busy signal. Asshown in FIG. 46, the DCD 420 at step S401 detects whether a busy signalfrom the copier 400 is received. When the busy signal is received, thecontrol of the DCD 420 is transferred to a polling process. When thecopier 400 has no transmission data upon the selecting, the copier 400does not output a busy signal. When the copier 400 determines that itcan respond to the selecting, the copier 400 outputs an acknowledgment(ACK). The DCD 420 at step S402 detects whether an ACK from the copier400 is received. When the ACK is received by the DCD 420, the DCD 420 atstep S405 transmits a message to the copier 400. After the message istransmitted to the copier 400, the copier 400 outputs anend-of-transmission (EOT) signal. The DCD 420 at step S406 detectswhether the EOT signal from the copier 400 is received. After the EOTsignal is received by the DCD 420, the selecting process is terminatedand the control of the DCD 420 is transferred to the polling process.

When the copier 400 determines that it cannot respond to the selecting,the copier 400 outputs a negative acknowledgment (ACK). The DCD 420 atstep S403 detects whether a negative ACK from the copier 400 isreceived. When a negative ACK is not received, the DCD 420 at step S404detects whether a time-out period has elapsed since the start of theselecting. When the time-out period has elapsed, the selecting processis terminated, and the control of the DCD 420 is transferred to thepolling process.

4.3.2 Control of Communications from Copier to CSS or Communicationsfrom Copier to DCD

When a significant failure of the copier 400 takes place, the copier 400immediately transmits a remote message (or an emergency message) to theDCD 420 or to the CSS 460 through the PSN 450. The remote messagenotifies that the failure of the copier 400 has occurred.

The copier 400 has a service program mode in addition to an imageformation mode. When the image formation mode of the copier 400 isshifted to the service program mode by pressing a given mode shift key,the copier 400 immediately transmits a remote message (or an emergencymessage) to the DCD 420 or to the CSS 460 through the PSN 450. Theremote message notifies that the service program mode of the copier 400has started.

When the current copy count of the copier 400 reaches a predeterminednumber of copy sheets, the copier 400 immediately transmits a remotemessage (or an emergency message) to the DCD 420 or to the CSS 460through the PSN 450. The remote message notifies that a copy sheetreplenishment is requested by the copier 400.

The DCD 420 periodically performs a polling to the image forming devices400 at regular intervals so as to detect whether a request from any ofthe image forming devices 400 is sent to the DCD 420. When the pollingto the image forming device 400 is performed by the DCD 420, one of theabove-mentioned controls is carried out in the image forming devicemanagement system of the present embodiment.

FIG. 47 shows a polling process performed to the image forming devices400 by the DCD 420. Suppose that the image forming devices 400 haverespective device codes and a specific control code indicating apredetermined polling function is assigned.

At the start of the polling process, the DCD 420 sends the specificcontrol code and the device code through the serial CCU to one of theimage forming devices 400 (which will be called the copier 401). Thecopier 401 receives the specific control code and the device code. Afterthe specific control code is detected, the copier 401 determines whetherthe received device code matches a device code of the copier 401. Whenthe received device code matches the device code of the copier 401, thecopier 401 recognizes that the polling of the DCD 420 is performed tothe copier 401. Instead of the specific control-code, a combination ofcertain codes may be used to indicate the predetermined pollingfunction.

As shown in FIG. 47, the DCD 420 at step S411 detects whether an EOTsignal from the copier 401 is received. When the EOT signal is received,the DCD 420 terminates the polling to the copier 401, and the control ofthe DCD 420 is transferred to a polling to the copier 402. When an EOTsignal from the copier 401 is not received, the DCD 420 at step S412detects whether a transmission request sent by the copier 401 isreceived. When the request is not received by the DCD 420, the DCD 420at step S413 detects whether a time-out period has elapsed since thestart of the polling to the copier 401. When the time-out period haselapsed, the polling to the copier 401 is terminated, and the control ofthe DCD 420 is transferred to the polling to the copier 402.

4.3.3 Control by DCD

The DCD 420 in the present embodiment can read out a total copy countfrom one of the image forming devices 400. The DCD 420 can transmit aresponse, sent by one of the image forming devices 400, through the PSN450 to the CSS 460.

When the selecting to a particular one of the image forming devices 400is performed by the DCD 420 at regular intervals, the reading of a totalcopy count from the particular one of the image forming devices 400 iscarried out by the DCD 420. The DCD 420 includes a plurality of memoriesfor storing respective total copy counts read from the image formingdevices 400. The DCD 420 transmits the total copy count, retained in oneof the memories, through the PSN 450 to the CSS 460 at regularintervals.

4.4 Control Part of Image Forming Device

FIG. 48 shows a control part of each image forming device 400 in thepresent embodiment.

As shown in FIG. 48, the control part of the image forming device 400includes a controller 511 which generally has a CPU 500, a bus 501, areal-time (R/T) clock 510, a ROM 502, a RAM 503, a non-volatile (N/V)RAM 504, an input/output (I/O) port 505, a first serial CCU 506, asecond serial CCU 507, and a third serial CCU 508. Further, the controlpart of the image forming device 400 includes a PI (personal interface)509. The elements of the controller 511 and the PI 509 areinterconnected by the bus 501.

The CPU 500 executes a control program. The ROM 502 stores the controlprogram and control data therein. The RAM 503 provides a working storagearea for the CPU 500 when executing the control program. Thenon-volatile RAM 504 retains operating parameters by using a battery inthe non-volatile RAM 504, transmission data exchanged between the imageforming devices 400 and the CSS 460, device codes and ID codes of theimage forming devices 400, a telephone number of the CSS 460, the numberof redials, and a redial period are stored. The real-time (R/T) clock510 provides a current time.

The I/O port 505 has an output connected to various motors, solenoidsand clutches of the image forming device 400, and has an input connectedto various sensors and switches of the image forming device 400. Thefirst serial CCU 506 provides an interface between the CPU 500 and anoperation part (not shown) of the image forming device 400. The secondserial CCU 507 provides an interface between the CPU 500 and a documentfeeder (not shown) of the image forming device 400. The third serial CCU508 provides an interface between the CPU 500 and a copy postprocesspart (not shown) of the image forming device 400.

The PI 509 provides an interface between the CPU 500 and the DCD 420. Ifthe processing ability of the CPU 500 is adequately high, the functionsof the PI 509 may be incorporated in the CPU 500.

The main functions of the PI 509 are (1) the monitoring of a polling orselecting of the DCD 420, (2) the processing of an acknowledgment or anegative acknowledgment to the DCD 420, (3) the check of correctness ofa message transmitted to or received from the DCD 420, the parity checkand the error detection, and (4) the processing of a header of a messagetransmitted to or received from the DCD 420.

4.4.1 Structure of Personal Interface

FIG. 49 shows the PI (personal interface) 509 in the control part of theimage forming device 400 in the present embodiment.

As shown in FIG. 49, the PI 509 includes a CPU 600, a local bus 602, adual-port memory 602, a plurality of registers 603 through 606, an inputport 607, a device code setting switch 608, and a serial communicationinterface unit 609.

The CPU 600 is a one-chip microcomputer including a central processingunit, a ROM and a RAM. The CPU 600 controls the elements of the PI 509.The dual-port memory 602 can be accessed by both the CPU 600 of the PI509 and the CPU 500 of the image forming device 500. The dual-portmemory 602 is used when exchanging a message between the PI 509 and thecontroller 511. The registers 603 through 607 are used for controllingthe elements of the PI 509 when exchanging a message between the PI 509and the controller 511.

The device code setting switch 608 is provided in the PI 509 of eachimage forming device 400 to set a specific device address of the imageforming device 400. The specific device code of each image formingdevice 400 is used to identify the image forming device 400 when apolling or selecting of the DCD 420 is performed. The serialcommunication interface unit 609 is connected to the DCD 420 or the PI509 of a different image forming device 400.

4.5 Control Panel

FIG. 50 shows a control panel 701 of the image forming device 400 in thepresent embodiment. The control panel 701 includes a control part whichis essentially the same as the control part of the image forming device400 shown in FIG. 48.

As shown in FIG. 50, the control panel 701 includes ten keys 710, aclear/stop key 711, a print key 709, an enter key 712, an interrupt key713, a preheat/mode clear key 714, a mode check key 704, a screen changekey 705, a call key 706, a registration key 707, a guidance key 708, adisplay contrast volume 703, and a character display part 702.

4.5.1 Character Display Part

FIG. 51 shows the character display part 702 in the control panel 701 ofthe image forming device 400 of FIG. 50.

The character display part 702 of FIG. 51 is prepared by using full-dotliquid crystal display elements with a matrix touch-panel switch of atransparent sheet material attached thereto. In the matrix touch-panelswitch, a number of touch sensors (provided for each of 8×8 pictureelements) are internally provided. A key of the character display part702 is turned ON or OFF by pressing or touching it. In addition,indication of an operating state of the image forming device 400, suchas “copy possible”, “during coping” or “no paper”, is displayed on thecharacter display part 702 of the image forming device 400.

4.6 Data Format of Messages

FIG. 52 shows a data format of a message transmitted between the CSS 460and the DCD 420 in the fourth embodiment.

As shown in FIG. 52, the message includes an SYN 910, an SOH 920, an SN930, an STX 940, a text 950, an ETB or ETX 960, and an LRC 970. The text950 is exchanged between the CSS 460 and the DCD 420 together with theSYN 910, the SOH 920, the SN 930, the STX 940, the ETB or ETX 960, andthe LRC 970. The SN (serial number) 930 indicates a transmission blocknumber of the message within blocks of one transmission. One of numeralvalues “00” through “99” is sequentially assigned to the SN 930 of eachblock.

The text 950 includes an ID code 951, a type code 952, and a number ofrecords 953 (including records 953(1) through 953(N)). Each of therecords 953 includes a parameter code 955, the number of digits 956, anda data 957. The ID code 951 is used to identify a particular one of theimage forming device 400 and the DCD 420. The type code 952 includes aprocess code, and a text originating device ID and a text receivingdevice ID added thereto. The type code 952 is predetermined as in thefollowing table. TABLE 1 CODE PROCESS NAME DESCRIPTION 30 EMERGENCY AUTOR/M TRANSMISSION IN CASE OF CALL EMERGENCY 31 MANUAL CALL R/MTRANSMISSION WHEN MANUAL SWITCH IS TURNED ON 32 ALARM MESSAGE R/MTRANSMISSION WHEN ALARM MESSAGE OCCURS 22 BLOCK BILLING R/M TRANSMISSIONWHEN A PROCESS CONTRACT COPY COUNT IS REACHED 02 READ PROCESS READING OFDATA FROM COPIER 04 WRITE PROCESS WRITING OF DATA TO COPIER 03 EXECUTEPROCESS EXECUTION OF TEST BY R/M 08 DEVICE CODE PROCESS TO CHECK CHECKCOMMUNICATION FUNCTION

Each record 953, including the parameter code 955, the number of digits956 and the data 957, is predetermined as in the following table. TABLE2 CODE DESCRIPTION PARAMETER CODE INDICATES A KIND OF OPERA- TINGPARAMETER OF A COPIER NO. OF DIGITS INDICATES A LENGTH OF DATA WHICHFOLLOWS DATA THE CONTENTS OF EACH RECORD

As shown in FIG. 52, a separator 954 (which is a semicolon) is insertedbetween the ID code 951 and the type code 952, between the type code 952and the first record 953(1), and between the respective records 953.

FIG. 53 shows a data format of a message transmitted between the DCD 420and the PI 509.

As shown in FIG. 53, the message includes the SYN 910, the SOH 920, theSN 930, the STX 940, a text 950, the ETB or ETX 960, and the LRC 970.The text 950 includes a device code 958, a process code 959, and anumber of records 953 (including records 953(1) through 953(N)). Thedevice code 958 is a specific device address of each of the copiers 400set by the device code setting switch 608 of the PI 509 of each imageforming device 400. The correlation between the device code 958 and theID code 951 is retained in the non-volatile RAM of the DCD 420. Wheneach image forming device 400 is installed on a user site, the devicecode 958 is read from the image forming device 400 and transmitted tothe DCD 420.

The process code 959 is the same as the process code included in thetype code 952. The process code 959 is produced by eliminating the textoriginating device ID and the text receiving device ID from the typecode 952. Each of the records 953 in the message of FIG. 53 includes theparameter code 955, the number of digits 956, and the data 957, similarto that in the message of FIG. 52.

FIG. 54 shows a data format of a message transmitted between the PI 509and the image forming device 400 (or the controller 511). As shown inFIG. 54, the message is produced by eliminating the header, the devicecode and the parity portion from the message of FIG. 53 transmittedbetween the DCD 420 and the PI 509.

4.7 Block Billing Function

The block billing function is provided for the image forming devicemanagement system to establish a charge for a predetermined number ofcopy sheets as a contract for use of each image forming device 400. Toattain the block billing function, it is necessary that a precise copycount at a start of the block billing of each image forming device 400and a precise copy count at an end of the block billing be safelymanaged by the image forming device management system.

4.7.1 Block Billing Start Process

In the present embodiment, each of the image forming devices 400receives a non-resettable copy count and a remote message cycle, bothtransmitted to the image forming device 400 by the CSS 460 through theDCD 420 at a start of the block billing contract. The non-resettablecopy count indicates a predetermined number of copy sheets related tothe block billing contract for use of the image forming device 400. Theremote message cycle indicates a frequency at which the image formingdevice 400 transmits a remote message (including a block billing startcopy count) to the CSS 460. The transmission of the non-resettable copycount and the remote message cycle to the image forming device 400 iscarried out by using the selecting of the DCD 420 to the image formingdevice 400.

FIG. 55 shows a data format of a remote message transmitted between thePI 509 and the image forming device 400 when the image forming device400 receives the remote message (including a block billing start copycount) from the CSS 460.

As shown in FIG. 55, the data format of the message is essentially thesame as that of the message of FIG. 54. The message of FIG. 55 includesa process code 1201, a number of records 1202 (including records 1202(1)through 1202(N)), and the ETB or ETX. Each record 1202 includes aparameter code 1203, the number of digits 1204, and a data 1205.

The process code 1201 is set at “04” as listed in the TABLE 1 above. Theparameter code 1203 of the record 1202(1) indicates a kind of anoperating parameter (or a block billing start copy count). The number ofdigits 1204 is set at “08” in ASCII code. The data 1205 is set at theblock billing start copy count, and this data is written to the memoryof the image forming device 400 as the non-resettable copy count. Therecord 1202(1) carrying the non-resettable copy count is transmittedfrom the CSS 460 through the PI 509 to the image forming device 400.Similarly, the record 1202(2) carrying the remote message cycle istransmitted from the CSS 460 through the PI 509 to the image formingdevice 400.

The non-resettable copy count and the remote message cycle, bothtransmitted to the image forming device 400 by the CSS 460 through theDCD 420 at a start of the block billing contract, are processed by theCPU 500 of the image forming device 400 and stored in the non-volatileRAM 504. Hence, the CPU 500 acts as a receiving means for receiving thenon-resettable copy count and the remote message cycle, and thenon-volatile RAM 504 acts as a first storage means for storing thenon-resettable copy count and the remote message cycle. Further, the CPU500 acts as a control means for setting the image forming device 400 ina remote message enable state when a difference between a current copycount and the received copy count reaches an integral multiple of theremote message cycle. The CPU 500 acts as a remote message means fortransmitting a remote message through the DCD 420 to the CSS 460 afterthe image forming device 400 is set in the remote message enable state.The non-volatile RAM 504 acts as a second storage means for storing acurrent copy count that is incremented every time an image formation ofone copy sheet is performed by the image forming device 400.

FIG. 56 shows a block billing process performed by the CPU 500 of theimage forming device 400 in the present embodiment.

In the present embodiment, suppose that a paper-out (P/O) sensor (notshown) for sensing an ejection of a copy sheet out of the image formingdevice 400 is connected to an input of the I/O port 505, and outputs aP/O sensor signal to the CPU 500 via the I/O port 505.

As shown in FIG. 56, at the start of the block billing process, the CPU500 at step 1301 determines whether the image forming device 400 is inan image forming state. When the image forming device 400 is in an imageforming state, the CPU 500 at step 1302 determines whether the P/Osensor signal is at its falling edge. When the result at the step 1302is affirmative, the CPU 500 at step 1303 increments the current copycount of the image forming device 400. The CPU 500 at step 1304determines whether a difference between the current copy count and thereceived copy count (or the block billing start copy count) reaches anintegral multiple of the remote message cycle.

In the step 1304, it is determined whether the following calculation (orthe division) results in an integer:(the current copy count−the received copy count)/(the remote messagecycle)  (1)

When the result at the step 1304 is affirmative, the CPU 500 at step1305 sets a remote message (R/M) flag to “1” (or an ON state). After thestep 1305 is performed, the CPU 500 ends the block billing process ofFIG. 56.

When the result at the step 1301 is negative (or the image formingdevice 400 stops the image formation), the CPU 500 at step 1306determines whether the R/M enable flag is equal to “1”. When the resultat the step 1306 is affirmative, the CPU 500 at step 1307 transmits aremote message through the DCD 420 to the CSS 460. The transmission ofthe message is carried out by using a selecting of the DCD 420. Afterthe step 1307 is performed, the CPU 500 at step 1308 resets the R/Menable flag to “0” (or an OFF state). After the step 1308 is performed,the CPU 500 ends the block billing process.

In the block billing process of FIG. 56, the image forming device 400 isunable to perform the automatic message transmission during the imageformation. However, if the ability of the image forming device 400,including the CPU 500, is adequately high, it is possible to perform theautomatic message transmission even when the image forming device 400 isin the image forming state. In such a case, the setting of the R/Menable flag to “1” or “0” is not needed.

4.7.2 Data Format of Remote Message

FIG. 57 shows a data format of a remote message transmitted between thePI 509 and the image forming device 400 when the step 1307 in the blockbilling process of FIG. 56 is performed. The data format of the remotemessage is essentially the same as that of the message of FIG. 54.

As shown in FIG. 57, the remote message includes a process code 1401, anumber of records 1402 (including records 1402(1) through 1402(N)), andthe ETB or ETX. Each record 1402 includes a parameter code 1403, thenumber of digits 1404, and a data 1405.

The process code 1401 is set at “22” as listed in the TABLE 1 above. Theparameter code 1403 of the record 1402(1) indicates a kind of anoperating parameter (or a block billing start copy count). The number ofdigits 1404 is set at “01” in ASCII code. The data 1405 is set at theblock billing start copy count is set at “1”, and this data indicates anoccurrence of a remote massage. The data 1405 when the automatic messagetransmission is performed is always set at “1”, and “0” is not used forthe data 1405. The records 1402(2) through 1402(N) may be omitted ifthey are not needed.

A description of the data formats of a remote message transmittedbetween the PI 509 and the DCD 420 and a remote message transmittedbetween the DCD 420 and the CSS 460 will be omitted. Similar to the dataformat of the remote-message of FIG. 57, the data formats of theseremote messages may be defined.

4.7.3 Block Billing End Process

A block billing end process performed by the CPU 500 of the imageforming device 400 in the present embodiment is essentially the same asthe block billing process of FIG. 56 except that the block billing startcopy count of the latter process is substituted by a block billing endcopy count.

At the start of the block billing end process, the CPU 500 at step 1301determines whether the image forming device 400 is in an image formingstate. When the image forming device 400 is in an image forming state,the CPU 500 at step 1302 determines whether the P/O sensor signal is atits falling edge. When the result at the step 1302 is affirmative, theCPU 500 at step 1303 increments the current copy count of the imageforming device 400. The CPU 500 at step 1304 determines whether adifference between the current copy count and the received copy count(or the block billing end copy count) reaches an integral multiple ofthe remote message cycle.

In the step 1304, it is determined whether the following calculation (orthe division) results in an integer:(the received copy count−the current copy count)/(the remote messagecycle)  (2)

When the result at the step 1304 is affirmative, the CPU 500 at step1305 sets the remote message (R/M) flag to “1” (or the ON state). Afterthe step 1305 is performed, the CPU 500 terminates the block billing endprocess.

When the result at the step 1301 is negative (or the image formingdevice 400 stops the image formation), the CPU 500 at step 1306determines whether the R/M enable flag is equal to “1”. When the resultat the step 1306 is affirmative, the CPU 500 at step 1307 transmits aremote message through the DCD 420 to the CSS 460. The transmission ofthe remote message is carried out by using a selecting of the DCD 420.After the step 1307 is performed, the CPU 500 at step 1308 resets theR/M enable flag to “0” (or the OFF state). After the step 1308 isperformed, the CPU 500 terminates the block billing end process.

According to the block billing process and the block billing end processin the above-described embodiment, the image forming device 400 is setin the remote message enable state only when the difference between thecurrent copy count and the received copy count reaches an integralmultiple of the remote message cycle. The CPU 500 transmits a remotemessage to the CSS 460 after the image forming device 400 is set in theremote message enable state. It is possible for the image forming devicemanagement system of the present embodiment to efficiently carry out aprecise block billing function.

FIG. 58 shows another data format of the remote message transmittedbetween the PI 509 and the image forming device 400 when the step 1307in the block billing process of FIG. 56 is performed. The data format ofthe remote message is essentially the same as that of the remote messageof FIG. 57.

As shown in FIG. 58, the record 1402(1) of this remote message is thesame as that of the remote message of FIG. 57. A parameter code 1406 ofthe record 1402(2) indicates a kind of an operating parameter (or thecurrent copy count). The number of digits 1407 of the record 1402(2) isset at “08” in ASCII code. A data 1408 of the record 1402(2) is set atthe current copy count. The records 1402(3) through 1402(N) may beomitted if they are not needed.

A description of the data formats of a remote message transmittedbetween the PI 509 and the DCD 420 and a remote message transmittedbetween the DCD 420 and the CSS 460 will be omitted. Similar to the dataformat of the remote message of FIG. 58, the data formats of theseremote messages may be defined.

4.8 Display of User-Program Mode Indication

In the present embodiment, at least one of the current copy count, thecontract start copy count (or the block billing start copy count) andthe contract end copy count (or the block billing end copy count) isdisplayed on the character display part 702 in the control panel 701 ofthe image forming device 400. It is possible for the present embodimentto provide an easy-to use management operation for the user of the imageforming device 400.

FIG. 59 shows a user-program mode indication (or a block billingindication) displayed on the character display part 702 in the controlpanel 701 of the image forming device 400.

The image forming device 400 in the present embodiment may be shifted toa user-program mode, and during the user-program mode the user canperform a setting of a special operating parameter of the image formingdevice 400 which cannot be performed in the image formation mode. Forexample, the image formation mode of the image forming device 400 may beshifted to the user-program mode when the user manually inputs a secretnumber to the CPU 500 by pressing the ten keys 710, the clear/stop key711, the enter key 712 and/or the preheat/mode clear key 714.Alternatively, a block billing key for the above purpose may be providedin the control panel 701 of the image forming device 400 or may bedisplayed on the character display part 702 of the image forming device400.

In the example of the block billing indication shown in FIG. 59, thecurrent copy count and the contract end copy count are displayed on thecharacter display part 702 in the control panel 701 of the image formingdevice 400. The current copy count and the contract end copy count areread from the non-volatile RAM 504 by the CPU 500, and they aretransmitted through a display control part (not shown) to the characterdisplay part 702 by the CPU 500, so that the block billing indication isdisplayed.

5. Fifth Embodiment

The present embodiment of the image forming device management system ischaracterized in that the CSS 460 transmits a parameter code, indicatinga kind of a particular one of the operating parameters, through the DCD420 to the image forming device 400, and the image forming device 400determines, in response to an access request, an absolute address of thememory of the image forming device 400 by the parameter code, andaccesses the particular one of the operating parameters in the memory atthe absolute address.

The present embodiment is characterized in that the image formingdevices are of different models and share a common parameter codeindicating an identical kind for the operation parameters of theindividual image forming devices regardless of the model of each imageforming device.

In the present embodiment, the structure of the image forming devicemanagement system, the structure of the image forming device 400, thestructure of the DCD 420, the structure of the CSS 460, thecommunication sequences, and the data format of messages are essentiallythe same as corresponding elements of the previous embodiment describedin the above sections 4.1 through 4.6. A description will now be givenof only features of the fifth embodiment of the image forming devicemanagement system which are different from those of the previousembodiment.

5.1 Structure of System

FIG. 60 shows a fifth embodiment of the image forming device managementsystem.

The system of FIG. 60 is different from the system of FIG. 44 in thattwo DCD devices 420 and 421 are provided, one group 400 of image formingdevices 401 and 402 is connected through the DCD 420 to the CSS 460, andanother group 410 of image forming devices 411 through 413 is connectedthrough the DCD 421 to the CSS 460. Hereinafter, one of these imageforming devices will be called the image forming device 400 or thecopier 400 for the sake of convenience. Other structure of the system ofFIG. 60 are essentially the same as that of the system of FIG. 44. Theelements of the system of FIG. 60 which are the same as correspondingelements in FIG. 44 are designated by the same reference numerals, and adescription thereof will be omitted.

5.2 Memory Address

In the image forming device 400, a parameter code table is stored in theROM 502. In accordance with the data format of the message shown in FIG.54, respective memory addresses of the ROM 502 for storing the operatingparameters of the image forming device 400 are predetermined. In theparameter code table, respective parameter codes corresponding to thememory addresses of the ROM 502 are provided, and each parameter codeindicates a kind of a particular one of the operating parameters.

FIG. 61 shows a parameter code stored in the ROM 502 of the imageforming device 400. In the present embodiment, the image forming devicesare of different models and share a common parameter code indicating anidentical kind for the operation parameters of the individual imageforming devices regardless of the model of each image forming device.

5.3 Communication Sequences

FIG. 62A and FIG. 62B show respective communication sequences when aread request and a write request are transmitted to the image formingdevice 400 of concern by the CSS 460.

In each of the read request (FIG. 62A) and the write request (FIG. 62B),the copier 400 of concern receives an access request sent by the CSS460. By making reference to the parameter code table of the ROM 502 by aparameter code of the access request, the copier 400 determines anabsolute address of the memory of the copier 400 by the parameter code,and accesses a particular one of the operating parameters in the memoryat the absolute address. In the case of the read request, the copier 400reads out the operating parameter from the memory at the absoluteaddress, and transmits the read data through the DCD 420 to the CSS 460.In the case of the write request, the copier 400 writes data of thewrite request to the memory at the absolute address, and transmits thewritten data through the DCD 420 to the CSS 460.

5.4 Control Process of Copier

5.4.1 Main Control Process

FIG. 63 shows a main control process performed by the CPU 500 of theimage forming device 400 when an access request is transmitted to theimage forming device 400 by the CSS 460. The main control process ofFIG. 63 is essentially the same as the process of FIG. 20 except thatthe step S41 of the process of FIG. 20 is eliminated from the maincontrol process of FIG. 63.

5.4.2 Read Sub-Process

FIG. 64 shows a read sub-process S636 in the main control process ofFIG. 63. As shown in FIG. 64, the CPU 500 at step S641 gets a parametercode from the received read request. The CPU 500 makes reference to theparameter code table of the ROM 502 of the copier 400 by the parametercode. The CPU 500 at step S642 determines whether the received parametercode matches the parameter code table of the ROM 502. When the receivedparameter code matches the parameter code table, the CPU 500 at stepS643 determines whether the received parameter code indicates a readableoperating parameter by detecting a corresponding item of the parametercode in the parameter code table. When the received parameter codeindicates a readable operating parameter, the CPU 500 at step S644determines a memory address from the parameter code of the received readrequest by detecting a corresponding item of the parameter code in theparameter code table. The CPU 500 at step S645 transmits the data, readfrom the memory at the memory address, to the DCD 420. When the receivedparameter code does not indicate a readable operation parameter, the CPU500 at step S646 transmits an error code to the DCD 420.

5.4.3 Write Sub-Process

FIG. 65 shows a write sub-process S637 in the main control process ofFIG. 63. As shown in FIG. 65, the CPU 500 at step S651 gets a parametercode from the received write request. The CPU 500 makes reference to theparameter code table of the ROM 502 of the copier 400 by the parametercode. The CPU 500 at step S652 determines whether the received parametercode matches the parameter code table of the ROM 502. When the receivedparameter code matches the parameter code table, the CPU 500 at stepS653 determines whether the received parameter code indicates a writableoperating parameter by detecting a corresponding item of the parametercode in the parameter code table. When the received parameter codeindicates a writable operating parameter, the CPU 500 at step S654 getsa writing data from the received write request. The CPU 500 at step S655determines whether the writing data is in an effective data range. Whenthe writing data is in the effective data range, the CPU 500 at stepS656 determines a memory address from the parameter code of the receivedwrite request by detecting a corresponding item of the parameter code inthe parameter code table. The CPU 500 at step S657 writes the writingdata to the memory at the memory address. The CPU 500 at step S658transmits the written data (or the operating parameter), which iswritten to the memory at the memory address, to the DCD 420. When thereceived parameter code does not indicate a writable operationparameter, the CPU 500 at step S659 transmits an error code to the DCD420. When the writing data is not in the effective data range, the CPU500 performs the step S659.

6. Sixth Embodiment

The present embodiment of the image forming device management system ischaracterized in that the CSS 460 can manage an accurate maintenanceservice start time of each of the image forming devices 400. In thepresent embodiment, the basic structure of the image forming devicemanagement system is essentially the same as that of the previousembodiment described in the above sections 4.1 through 4.6. Adescription will now be given of only features of the sixth embodimentof the image forming device management system which are different fromthose of the previous embodiment.

6.1 Control Panel

FIG. 66 shows a control panel of the image forming device 400 in thepresent embodiment. As shown in FIG. 66, the control panel includes tenkeys 71, a clear/stop key 72, a print key 73, an enter key 74, aninterrupt key 75, a preheat/mode clear key 76, a mode check key 77, ascreen change key 78, a call key 79, a registration key 80, a guidancekey 81, a display contrast volume 82, and a character display part 83.

The character display part 83 is prepared by using full-dot liquidcrystal display elements with a matrix touch-panel switch of atransparent sheet material attached thereto. In the matrix touch-panelswitch, a number of touch sensors (provided for each of 8×8 pictureelements) are internally provided. A key of the character display part83 is turned ON or OFF by pressing or touching it. When a power switchof the copier 400 is turned ON, an image formation mode (copy mode)indication is displayed on the character display part 83. In addition,indication of an operating state of the image forming device 400, suchas “copy possible”, “during coping” or “no paper”, is displayed on thecharacter display part 83 of the image forming device 400.

FIG. 67 shows an image formation mode indication (or a copy modeindication) displayed on a character display part 83 of the controlpanel of the image forming device of FIG. 66.

As shown in FIG. 67, the copy mode indication includes a message displayarea 91, a set display area 92, a tray selection key/copy size displayarea 93, an auto sheet selection (ASS) key 94, a density adjusting key95, an auto density selection (ADS) key 96, an equal-size (E/S) key 97,an enlarge (E/L) key 98, and a reduce (R/D) key 99.

Further, in the copy mode indication of FIG. 67, a zoom key 83-100, asheet-designated sizing (SDS) key 83-101, a set of duplex mode keys83-102, a duplex mode message area 83-103, a pair of page-offset (P/O)keys 83-104, a page-offset mode message area 83-105, a shift functionselect key 83-106, a staple select key 83-107 (one place), a stapleselect key 83-108 (two places), and a maintenance end message key83-109. When requesting a transmission of a maintenance end message tothe CSS 460, the maintenance end message key 83-109 is pressed or turnedON by the user. The maintenance end message key 83-109 may be displayedonly when needed, and it may be eliminated when unneeded. In addition,the maintenance end message key 83-109 may be displayed only when thecopier 400 is shifted to a service program mode, which will be describedbelow.

6.2 Service Program Mode Process

Each image forming device 400 in the present embodiment may be shiftedto a service program mode, and during the service program mode aserviceman can perform a maintenance service of the image forming device400, such as setting or adjustment of the operating parameters of theimage forming device 400 or displaying of the statistical data of theimage forming device 400, which cannot be performed in the imageformation mode. For example, the image forming device 400 may be shiftedinto the service program mode when the serviceman manually inputs asecret number (not available to the user) to the CPU 500 by pressing theten keys 71 and/or the enter key 74 in a predetermined sequence.

FIG. 68 shows a service program (SP) mode indication displayed on thecharacter display part 83 of the control panel of the image formingdevice of FIG. 66 during the service program mode.

As shown in FIG. 68, the service program (SP) mode indication on thecharacter display part 83 includes an adjust mode shift key 111, a testmode shift key 112, a data output mode shift key 113, a specialspecification set mode shift key 114, a remote message test mode shiftkey 115, and a counter mode shift key 116.

In the present embodiment, when the ten keys 71 and/or the enter key 74of the control panel of the image forming device 400 are pressed orturned ON in a predetermined sequence by a serviceman, the image formingdevice 400 is shifted to the service program mode. When the imageforming device 400 is shifted to the service program mode, the serviceprogram mode indication (including a maintenance end message key) isdisplayed on the character display part 83 as shown in FIG. 68. At thesame time, the image forming device 400 automatically transmits amaintenance service start message through the DCD 420 to the CSS 460.The maintenance service start message notifies the CSS 460 of the startof a maintenance service of the image forming device 400 by theserviceman. FIG. 74A shows a data format of the maintenance servicestart message transmitted to the CSS 460 by the image forming device400.

During the service program mode, the maintenance service of the imageforming device 400 is performed by the serviceman. When the maintenanceservice is complete, the maintenance end message key of the serviceprogram mode indication on the character display part 83 by theserviceman. At this time, the image forming device 400 automaticallytransmits a maintenance service end message through the DCD 420 to theCSS 460. The maintenance service end message notifies the CSS 460 of theend of the maintenance service of the image forming device 400 by theserviceman. FIG. 74B shows a data format of the maintenance service endmessage transmitted to the CSS 460 by the image forming device 400.

According to the present embodiment, the CSS 460 can manage an accuratemaintenance service start/end time of each of the image forming devices400.

6.3 Service Program Mode Shift Check Process

FIG. 69 shows a maintenance service start message process performed bythe CPU 500 of the image forming device 400 in the present embodiment.

As shown in FIG. 69, the CPU 500 at step S691 determines whether aservice program mode shift key is pressed or turned ON by the serviceman(or determines whether the ten keys 71 and/or the enter key 74 of thecontrol panel of the image forming device 400 are pressed or turned ONin the predetermined sequence by the serviceman). When the result at thestep S691 is affirmative, the CPU 500 at step S692 shifts the imageforming device 400 to the service program mode. In the step S692, theCPU 500 displays the service program mode indication as shown in FIG. 68on the character display part 83 of the control panel. In the presentembodiment, the service program mode indication includes the maintenanceend message key (not shown in FIG. 68).

After the step S692 is performed, the CPU 500 at step S693 determineswhether a maintenance run flag is equal to “1”. When the result at thestep S693 is negative (or the maintenance run flag=“0”), the CPU 500 atstep S694 transmits a maintenance service start message through the DCD420 to the CSS 460. The maintenance service start message notifies theCSS 460 of the start of the maintenance service of the image formingdevice 400. After the step S694 is performed, the CPU 500 at step S695sets the maintenance run flag to “1”. After the step S695 is performed,the CPU 500 ends the maintenance service start message process of FIG.69.

When the result at the step S693 is affirmative (the maintenance runflag=“1”), the CPU 500 ends the maintenance service start messageprocess of FIG. 69. Hence, at this time, the CPU 500 inhibits theautomatic transmission of the maintenance service start message to theCSS 460. In this case, the automatic transmission of the maintenanceservice start message is already performed but the service program modeshift key mentioned above is pressed or turned ON again by theserviceman. Also, the automatic transmission of a maintenance serviceend message is not yet performed by pressing the maintenance end messagekey. Hence, it is possible for the image forming device managementsystem of the present embodiment to manage an accurate maintenanceservice start time of the image forming device 400.

6.4 Maintenance Service End Message Process

FIG. 70 shows a maintenance service end message process performed by theCPU 500 of the image forming device 400 in the present embodiment. Themaintenance service end message process of FIG. 70 is initiated when themaintenance end message key of the service program mode indication onthe character display part 83 is pressed or turned ON by the serviceman.

As shown in FIG. 70, the CPU 500 at step S702 transmits a maintenanceservice end message through the DCD 420 to the CSS 460. After the stepS701 is performed, the CPU 500 at step S702 rests the maintenance runflag to “0”. The image forming device management system of the presentembodiment can prevent the maintenance of a maintenance service end timefrom being degraded even when the serviceman fails to request thetransmission of the maintenance service end message to the CSS 460.Hence, it is possible for the image forming device management system ofthe present embodiment to manage an accurate maintenance service endtime of each of the image forming devices 400.

6.5 Maintenance Service Start Message Process

FIG. 71 shows a maintenance service start message key displayed on thecharacter display part 83 of the control panel of the image formingdevice 400.

In the present embodiment, when the ten keys 71 and/or the enter key 74of the control panel of the image forming device 400 are pressed orturned ON in a predetermined sequence by a serviceman, the maintenanceservice start indication (including the maintenance start message key120) is displayed on the character display part 83 as shown in FIG. 71.When the maintenance start message key 120 in the maintenance servicestart indication, displayed on the character display part 83, is pressedor turned ON by the serviceman, the image forming device 400 is shiftedto the service program mode. When the image forming device 400 isshifted to the service program mode, the service program mode indication(including the maintenance end message key) is displayed on thecharacter display part 83 as shown in FIG. 68. At the same time, theimage forming device 400 automatically transmits a maintenance servicestart message through the DCD 420 to the CSS 460. For example, FIG. 74Ashows a data format of the maintenance service start message transmittedto the CSS 460 by the image forming device 400 at this time. Themaintenance service start message notifies the CSS 460 of the start ofthe maintenance service of the image forming device 400 by theserviceman. It is possible for the image forming device managementsystem of the present embodiment to manage an accurate maintenanceservice start time of each of the image forming devices 400.

During the service program mode, the maintenance service of the imageforming device 400 is performed by the serviceman. When the maintenanceservice is complete, the maintenance end message key of the serviceprogram mode indication on the character display part 83 is pressed orturned ON by the serviceman. At this time, the image forming device 400automatically transmits a maintenance service end message through theDCD 420 to the CSS 460. The maintenance service end message notifies theCSS 460 of the end of the maintenance service of the image formingdevice 400 by the serviceman. For example, FIG. 74B shows a data formatof the maintenance service end message transmitted to the CSS 460 by theimage forming device 400 at this time.

According to the present embodiment, the CSS 460 can manage an accuratemaintenance service start/end time of each of the image forming devices400.

FIG. 72 shows a maintenance service start message process performed bythe CPU 500 of the image forming device 400 in the present embodiment.

As shown in FIG. 72, the CPU 500 at step S721 determines whether theservice program mode shift key is pressed or turned ON by the serviceman(or determines whether the ten keys 71 and/or the enter key 74 of thecontrol panel of the image forming device 400 are pressed or turned ONin the predetermined sequence by the serviceman). When the result at thestep S721 is affirmative, the CPU 500 at step S722 determines whetherthe maintenance run flag is equal to “1”.

When the result at the step S722 is negative (or the maintenance runflag=0), the CPU 500 at step S723 displays the maintenance service startindication of FIG. 71 on the character display part 83. As describedabove, the maintenance service start indication includes the maintenancestart message key 120. After the step S723 is performed, the CPU 500 atstep S724 determines whether the maintenance start message key 120 ispressed or turned ON by the serviceman. When the maintenance startmessage key 120 is turned ON, the CPU 500 at step S725 transmits themaintenance service start message through the DCD 420 to the CSS 460.After the step S725 is performed, the CPU 500 at step S726 sets themaintenance run flag to “1”. After the step S726 is performed, the CPU500 performs step S727 which will be described below.

When the result at the step S721 is negative (or the service programmode shift key is not turned ON), the CPU 500 performs step S727 whichwill be described below, and does not perform the steps S723-S726.

When the result at the step S722 is affirmative (or the maintenance runflag=“1”), the CPU 500 at step S727 shifts the image forming device 400into the service program mode. In the step S727, the CPU 500 displaysthe service program mode indication of FIG. 68 on the character displaypart 83 of the control panel. In the present embodiment, the serviceprogram mode indication includes the maintenance end message key (notshown in FIG. 68). After the step S727 is performed, the CPU 500 endsthe maintenance service start message process of FIG. 72. Hence, the CPU500 inhibits the automatic transmission of the maintenance service startmessage to the CSS 460 when the maintenance run flag is equal to “1”. Inthis case, the automatic transmission of the maintenance service startmessage is already performed but the service program mode shift keymentioned above is pressed or turned ON again by the serviceman. Also,the automatic transmission of a maintenance service end message is notyet performed by pressing the maintenance end message key. Accordingly,it is possible for the image forming device management system of thepresent embodiment to manage an accurate maintenance service start timeof each of the image forming devices 400.

6.6 Maintenance Service End Key Check Process

As described above, during the service program mode, the maintenanceservice of the image forming device 400 is performed by the serviceman.When the maintenance service is complete, the maintenance end messagekey of the service program mode indication on the character display part83 is pressed or turned ON by the serviceman. At this time, the imageforming device 400 automatically transmits a maintenance service endmessage through the DCD 420 to the CSS 460. The maintenance service endmessage notifies the CSS 460 of the end of the maintenance service ofthe image forming device 400 by the serviceman.

In the present embodiment, only when the maintenance run flag is set to“1”, the maintenance end message key of the service program modeindication is displayed on the character display part 83.

FIG. 73 shows a maintenance service end message process performed by theCPU 500 of the image forming device 400 in the present embodiment.

As shown in FIG. 73, the CPU 500 at step S731 determines whether themaintenance run flag is equal to “1”. When the result at the step S731is negative (or the maintenance run flag=0), the CPU 500 at step S732eliminates the maintenance end message key from the character displaypart 83, regardless of the current condition of the service program modeindication displayed on the character display part 83. After the stepS732 is performed, the CPU 500 ends the maintenance service end messageprocess of FIG. 73. Hence, when the maintenance run flag is equal to“0”, the automatic transmission of the maintenance service end messageis inhibited.

When the result at the step S731 is affirmative (or the maintenance runflag=1), the CPU 500 at step S733 displays the maintenance end messagekey on the character display part 83, regardless of the currentcondition of the service program mode indication displayed on thecharacter display part 83. After the step S733 is performed, the CPU 500at step S734 determines whether the maintenance end message key ispressed or turned ON by the serviceman.

When the result at the step S734 is negative, the CPU 500 ends themaintenance service end message process of FIG. 73. On the other hand,when the result at the step S734 is affirmative, the CPU 500 at stepS735 transmits the maintenance service end message through the DCD 420to the CSS 460. After the step S735 is performed, the CPU at step S736resets the maintenance run flag to “0”. After the step S736 isperformed, the CPU 500 ends the maintenance service end message processof FIG. 73. Hence, it is possible for the image forming devicemanagement system of the present embodiment to manage an accuratemaintenance service end time of each of the image forming devices 400.

Further, the present invention is not limited to the above-describedembodiments, and variations and modifications may be made withoutdeparting from the scope of the present invention.

1. An image forming device management system including: a plurality of image forming devices, each of the image forming devices having operating parameters stored in a memory of the image forming device, and absolute addresses of the memory where the respective operating parameters are stored being predetermined according to a kind of each operating parameter; a central service station for reading information from or writing information to the operating parameters of one of the image forming devices by transmitting an access request to said one of the image forming devices; and a communication device for connecting one of the image forming devices to the central service station via a communication network, wherein the central service station comprises parameter code transmitting means for transmitting a parameter code, indicating a kind of a particular one of the operating parameters, through the communication device to one of the image forming devices when transmitting an access request to said one of the image forming devices, and wherein each of the image forming devices comprises: address determination means responsive to the access request for determining an absolute address of the memory of the image forming device in accordance with the parameter code transmitted by said code transmitting means; and access request processing means for accessing the particular one of the operating parameters at the absolute address of the memory determined by the address determination means.
 2. The system according to claim 1, wherein the image forming devices are of different models, and share a common parameter code indicating an identical kind for the operating parameters of the individual image forming devices regardless of the model of each image forming device. 